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to  diffuse 
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,e  respects 

>rtance  in 
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it,  is  fully 
^t  the  textlnayrbe"clearly  and  readily  understood 
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I.  Hearing,  and  How  to  Keep  Bt, 

By  CHAS.  H.  BURNETT,  M.D.,  of  Philadelphia, 

Consulting  Aurist  to  the  Fennsytvaiiia  Institution  for  the  Deaf  and  Dumb, 
Aurist  to  the  Presbyteriaji  Hospitat,  etc. 

II.  Long  Life,  and  How  to  Reach  It, 

By  J.  G.  RICHARDSON,  M.D.,  of  Philadelphia, 

Professor  of  Jnygieji»iti  the  University  of  Fen7isylvania,  etc. 

III.  The  Summer  and  its  Diseases, 

By  JAMES  C.  WILSON,  M.D.,of  Philadelphia, 
Lecturer  on -Physical  Diagnosis  in  fefferson  Medicat  College,  etc, 

IV.  Eyesight"^,  and  How  to  Care  for  It, 

By  GEORGE  C.  HARLAN,  M.D.,  of  Philadelphia, 

Surgeon  to  the  Wilts  \Eyej  Hospitat. 

V.  The  Throat  and  the  Voice, 

By  J.  SOLIS  COHEN,  M.D.,  of  Philadelphia, 

Lecturer  on  Diseases  of  the  Throat  di  feff^erson  Alcdicat  College. 

VI.  The  Winter  and  its  Dangers, 

By  HAMILTON  OSGOOD,  M.D.,  of  Boston, 

Editorial  Staff  Boston  JMedical  a?td  Siugical  Journal, 

VII.  The  IVlouth  and  the  Teeth, 

By  J.  W.  WHITE,  M.D.,  D.D.S,,  of  Philadelphia, 

Editor  of  the  Dental  Cosmos. 

VIII.  Our  Homes,  •: 

By  HENRY  HARTSHORNE,  M.D.,  of  Philacfc^hia,  •    .;  ; 

Formerly  Professor  of  Hygiene  in  the  University  oj  Pennsylvania. ' 

IX.  The  Skin  in  Health  and  Disease,^ 

By  L.  D.  BULKLEY,  M.D. ,  of  New  York,    '■ 

Physiciati  to  the  Sfiin  Departi/tent  if  the  Demilt  Dispensary  and  of  the  ■ 
A'eii)  York  Hospital. 

X.  Brain  Woric  and  Overwortc, 

By  H.  C.  WOOD,  Jr.,  M.D.,  of  Philadelphia, 

Clinical  Professor  of  Nervous  Diseases  in  the  University  of  P'ennsylvania,  etc. 

XI.  Sea-Air  and  Sea-Bathing, 

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Surgeon  to  ttie  Episcopal  Hospital. 

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http://www.archive.org/details/mouthteethOOwhit 


AMERICAN  HEALTH  PRIMERS. 


EDITED   BY 


W.  W.    KEEN,    M.D., 

Fellow  of  the  College  of  Physicians  of  Philadelphia, 
AND  Surgeon  to  St.  Mary's  Hospital. 


^  *#. 


'•^v 


AME^^J^CAN  H-EALTH  PRIMERS. 

.1  \    £^ ^, 


M.^* 
^   ^ 


86 


'^'y 


t.% 


Mouth  and  the  Teeth. 


% 


BY 

J.  W.  WHITE,  M.D.,  D  D.S., 

Editor  of  the  Dental  Cosmos. 


i 


PHILADELPHIA: 
LINDSAY   &   BLAKISTON. 

1879. 


Vi/  «w  C. 


Copyright. 
LINDSAY  &  BLAKISTON. 

1879. 


CONTENTS. 


CHAPTER 

I.  Introductory 


II.  The  Mouth 

III.  Anatomy  of  the  Teeth 

IV.  Development  of  the  Teeth 

V.  Eruption  of  the  Temporary  Teeth   . 
VI.  Difficult  Dentition       .... 
VII.  Care  of  the  Temporary  Teeth  . 
VIII.  Sixth-Year  Molars         .... 
IX.  Shedding    of   the  Temporary  and   Erup 

TION   OF   THE   PERMANENT   TeETH 

X.  Nutrition  of  the  Teeth 
XI.  Food  in  its  Relations  to  the  Teeth 
XII.  Nervous  Relations  of  the  Teeth 

XIII.  Constitutional    Peculiarities,  Varieties 

AND  Defects  of  the  Teeth 

XIV.  Irregularities  of  the  Teeth 

I  *  V 


9 
13 
32 
44 
47 
50 
60 

64 

68 
76 
78 
84 

94 
98 


VI  CONTENTS. 

CHAPTER  PAGE 

XV.  Tartar,  or  Salivary  Calculus        .        .  io6 


XVI.  Decay  of  the  Teeth,  or  Caries     . 
XVII.  Toothache — Extraction — Hemorrhage 
XVIII.  Hygiene  of  the  Mouth    . 

XIX.  Reparative  Treatment     . 
XX.  Substitution  —  Artificial  Dentures 


no 
117 
126 
138 
143 


DIAGRAM  OF  FOOD  AND  AIR  TRACTS. 


The  solid  line  throuth  Mouth  and  Gullet  represents  the  course 
taken  by  food  and  drink ;  the  dotted  lines  through  Mouth, 
Nasal  Passages,  and  Air- Tube  represent  the  course  taken  by 
the  air. 

viii 


THE 

MOUTH   AND   THE  TEETH. 


CHAPTER    J.  ___ 

INTRODUCTORvGEORGr     LVANS, 

THE  mouth  is  not  only  the  ^M^^^j^&liW^'ai'cf ''^^ 
characteristic,  but  it  is  also  the  most  important, 
of  all  the  features.     No  other  portion  of  the  human 
organism  is  of  such  complex  structure,  and  no  other 
has  such  diversified  functions  to  perform. 

The  preservation  of  the  health  of  the  mouth  is  es- 
sential to  the  general  well-being.  Disease  of  the 
body  involves  an  unhealthy  condition  of  the  mouth, 
and  is  manifested  by  perceptible  changes  in  the 
tongue,  gums,  lips,  and  mucous  membrane.  On  the 
other  hand,  it  is  reasonable  to  conclude  that  an  un- 
healthy condition  of  the  mouth  will  act  prejudicially 
to  the  general  health  of  the  organism.  The  breath, 
if  made  oifensive  by  a  diseased  state  of  the  mouth 
or  teeth,  cannot  be  wholesome  when  inhaled  into  the 
lungs  and  brought  into  contact  with  those  delicate 
structures,  the  air-cells ;  nor  can  it  exercise  the  best 

9 


lO  THE  MOUTH  AND    THE    TEETH. 

influence  upon  the  blood,  which  depends  in  great 
measure  for  its  quality  upon  the  purity  of  the  air 
supplied  to  the  lungs.  Moreover,  it  is  very  undesir- 
able to  transmit  offensive  matters  into  the  stomach,  as 
vitiated  saliva  or  food  polluted  by  noxious  secretions. 

The  value  of  a  good  set  of  teeth  —  a  complete  and 
perfect  "denture" — is  not  to  be  computed,  if  only 
the  service  of  dividing  and  masticating  the  food  be 
considered ;  mastication  being  the  first  step  in  a 
series  of  processes  by  which  the  food  is  transformed 
into  nourishment  adapted  to  the  needs  of  the  sys- 
tem. When  to  this  consideration  we  add  their  im- 
portance in  assisting  vocalization  —  distinctness  of 
utterance  in  speech  and  song  —  and  the  necessity  for 
their  preservation  in  order  to  maintain  the  natural 
symmetry  of  the  features,  it  would  appear  to  be  a 
positive  duty  that  every  one  should  study  to  avoid  the 
causes  which  tend  to  the  premature  destruction  of  the 
teeth. 

There  is  abundant  reason  for  an  effort  to  awaken  a 
general  interest  in  the  prevention  and  arrest  of  the 
process  of  decay  in  human  teeth.  That  there  has 
been  a  progressive  deterioration  in  the  quality  of  the 
dental  outfit  of  mankind  through  successive  genera- 
tions, is  claimed  by  many  observing  practitioners  of 
dentistry.  There  can  be  no  doubt  that  dental  caries 
is  on  the  increase  —  is  well-nigh  universal ;  while 
recession  of  the  gums  and  absorption  of  the  support- 


INTR  OD  UC  TOR  Y.  1 1 

ing  alveolar  processes  are  fearfully  prevalent,  even  in 
the  mouths  of  the  young.  If  these  tendencies  are  to 
be  successfully  combated,  it  must  be  not  alone  nor 
chiefly  through  the  manipulative  skill  of  dental  oper- 
ators, but  through  a  better  appreciation  by  the  people 
of  the  causes  of  the  deterioration  and  of  the  means 
by  which  it  may  be  counteracted.  The  importance 
of  a  wide  diffusion  of  information  in  regard  to  these 
matters  has  been  recognized  by  every  intelligent 
dentist.  It  is  high  time  that  more  attention  be  given 
to  the  subject. 

Matters  of  much  less  importance  to  personal  ap- 
pearance, of  vastly  less  account  to  individual  com- 
fort, and  beyond  all  question  of  smaller  moment  to 
health  and  life,  are  made  the  subjects  of  constant 
study  and  care ;  while  the  amount  of  information 
possessed  by  the  public  in  this  direction  is  lament- 
ably small,  and  much  of  that  is  erroneous.  Many 
otherwise  intelligent  people  are  sadly  deficient  in  a 
proper  comprehension  of  this  subject.  There  are  no 
other  organs  of  the  body  which  are  not  more  appre- 
ciated than  the  teeth,  and  yet  there  are  none  the 
neglect  of  which  entails  more  serious  results. 

It  is  estimated  that  twenty  millions  of  teeth  are 
annually  sacrificed  in  the  United  States.  The  crim- 
inal neglect  thus  exhibited  involves  not  only  this 
waste  of  teeth,  but  is  the  fruitful  cause  of  abscesses, 
facial  deformities,  neuralgias,  dyspepsias,  headaches, 


12  THE  MOUTH  AND    THE    TEETH. 

eye  and  ear  troubles,  and  other  morbid  conditions. 
Protracted  derangements  of  sight,  of  hearing,  and  of 
the  general  health  not  infrequently  have  their  unsus- 
pected origin  in  the  mouth. 

For  these  reasons,  the  facts  relating  to  the  forma- 
tion, structure,  development,  eruption,  character,  func- 
tions, and  diseases  of  the  teeth,  and  to  the  preservation 
of  their  health  and  that  of  the  associated  parts,  should 
be  better  and  more  generally  understood. 

In  the  hope  of  awakening  interest  and  stimulating 
thought  with  reference  to  the  intelligent  care  of  the 
mouth  this  monograph  has  been  prepared. 


CHAPTER    II. 

THE    MOUTH. 

THE  mouth  is  the  organ  of  taste,  of  speech,  of 
song,  of  mastication,  and  of  insalivation ;  the 
avenue  for  the  entrance  of  the  food  and  drink  essen- 
tial to  life,  and  the  channel  through  which  passes 
much  of  the  air  which  is  inhaled,  as  well  as  that 
which  is  expired.  The  same  membrane  which  lines 
its  cavity  is  continued  throughout  the  nose,  the 
throat,  the  stomach,  and  the  intestinal  canal;  through- 
out the  larynx,  the  windpipe,  the  bronchial  tubes,  and 
the  lungs.  It  is  thus  closely  related  to  the  functions 
of  digestion  and  respiration,  while  by  open  passages 
direct  communication  is  maintained  with  the  eyes, 
ears,  and  nose,  and  by  the  nerves,  with  which  it  is 
abundantly  supplied,  with  every  part  of  the  body. 

The  mouth  is  made  up  of  the  lips,  cheeks,  upper 
and  lower  jaws,  with  their  alveolar  processes  ;  the 
hard  and  the  soft  palate,  the  tongue,  salivary  and 
mucous  glands,  mucous  membrane,  gums,  and  teeth. 
It  is  a  wonderful  combination  of  bones,  muscles, 
arteries,  veins,  nerves,  glands,  membranes,  and  a  cu- 

2  13 


14  THE   MOUTH  AND    THE    TEETH. 

rious  structure  of  hard  and  soft  tissues  constituting  the 
teeth.  These,  like  ail  other  parts  of  the  body,  depend 
upon  the  general  system  for  their  development  and 
nourishment. 

The  lips,  which  are  fleshy  folds  surrounding  the 
orifice  of  the  mouth,  and  the  cheeks,  with  which  they 
are  continuous,  forming  the  sides  of  the  face  and  the 
boundaries  of  the  mouth,  are  composed  of  true  skin 
externally  and  mucous  membrane  internally,  between 
which  are  the  muscles  which  produce  their  move- 
ments; also,  blood-vessels,  nerves,  and  small  bodies 
called  mucous  glands,  having  ducts  or  tubes  opening 
by  minute  orifices  upon  the  inner  or  mucous  surfaces. 
These  glands  secrete  a  fluid  which  helps  to  lubricate 
the  mouth.  (By  the  terms ' '  secrete ' '  and  ' '  secretion, ' ' 
as  here  used,  is  meant  a  process  by  which  various 
matters  derived  from  the  blood  are  collected  and  dis- 
charged at  particular  points  in  order  afterwards  to  be 
employed  for  special  purposes  in  the  economy.) 

The  palate  or  roof  of  the  mouth,  well  shown  in 
the  Frontispiece  J  consists  of  two  portions  —  the  hard 
palate  in  front,  and  the  soft  palate  (called  the  velum) 
behind  it,  terminating  in  a  central  pendulous  structure 
—  the  uvula,  commonly  but  erroneously  called  the 
palate.  The  hard  palate,  which  is  a  bony  plate,  is 
covered  by  a  dense  tissue  called  the  periosteum  {^around 
a  bo7ie).  The  soft  palate  is  a  soft,  movable  fold  or 
curtain    of  mucous   membrane,    inclosing    muscular 


THE  MOUTH.  1 5 

fibres.  It  serves  important  purposes  in  the  mech- 
anism of  the  mouth,  assisting  materially  in  the  ar- 
ticulation of  sound,  in  the  act  of  swallowing,  and, 
conjointly  with  certain  muscles  connected  with  it  and 
with  the  tongue  and  pharynx,  preventing  the  passage 
of  food  into  the  nose,  which  opens  into  the  upper 
part  of  the  throat  above  the  soft  palate. 

The  tongue  is  a  muscular  body  lying  on  the  floor 
of  the  mouth  within  the  lower  dental  arch.  It  is  cov- 
ered by  mucous  membrane,  beneath  which  are  mucous 
glands  having  orifices  opening  upon  its  surface.  It 
is  the  organ  of  the  special  sense  of  taste,  and  presides 
over  the  processes  of  mastication  and  swallowing.  The 
exquisite  sensibilities  of  touch  and  taste  residing  in  the 
tongue  are  important  aids  in  mastication.  Its  sense 
of  taste  informs  us  of  the  qualities  of  the  food,  and 
its  sense  of  touch  recognizes  its  physical  condition  — 
consistency,  size,  form,  and  when  it  has  been  suffi- 
ciently masticated.  By  its  muscular  structure  it  col- 
lects and  moves  the  food  from  one  side  of  the  mouth 
to  the  other,  and,  with  the  aid  of  the  lips  and  cheeks, 
keeps  it  between  the  masticating  surfaces  of  the  teeth. 
When  the  food  is  in  a  sufficiently  softened  condition, 
the  tongue  collects  it  upon  its  upper  surface  and  passes 
it  backward  into  the  pharynx  —  a  funnel-shaped  canal 
situated  on  the  middle  line  in  front  of  the  spinal 
column,  between  the  base  of  the  skull  and  the  esoph- 
agus or  gullet  —  which  serves  as  a  common  origin  for 


1 6  THE  MOUTH  AND    THE    TEETH. 

the  digestive  and  respiratory  tracts,  giving  passage  to 
the  air  during  respiration  and  to  the  food  at  the  time 
of  deglutition  or  swallowing.  By  virtue  of  its  com- 
plicated muscular  structure  the  tongue  is  also  capable 
of  the  great  variety  of  movements  essential  to  suction 
and  to  speech.  At  the  base  of  the  tongue  is  a  cartila- 
ginous oval  or  triangular  flap  called  the  epiglottis,  its 
apex  attached,  the  other  and  larger  part  free.  Its 
special  use  seems  to  be  to  cover  the  glottis  (an  aper- 
ture in  the  larynx  or  the  apparatus  of  voice,  situated 
at  the  top  of  the  trachea  or  windpipe),  and  thus  pre- 
vent the  passage  of  food  into  the  air-tubes.  The 
tongue  sympathizes  with  all  derangements  of  the 
general  system  —  especially  with  those  of  the  ali- 
mentary canal.  As  an  index  of  the  state  of  the 
general  system,  it  affords,  doubtless,  more  varied 
information  than  any  other  single  means  of  judg- 
ment. Its  bulk,  color,  dryness  or  moisture ;  the 
character  of  its  surface,  of  its  coatings,  and  of  its 
movements  show  to  the  skilled  observer  the  degree, 
progress,  and  stage  of  systemic  derangement.  The 
tongue  is  liable  to  a  variety  of  local  diseases  and 
injuries.  Among  the  latter,  ulcers,  sometimes  very 
serious,  are  caused  by  the  persistent  irritation  of  the 
jagged  edge  of  a  broken  or  carious  tooth  or  a  project- 
ing root.  Similar  effects  from  like  causes  are  also 
produced  upon  the  cheeks.     Whenever  such  sources 


THE  MOUTH.  1 7 

of  irritation  are  recognized,  they  should  be  promptly 
corrected. 

Opening  upon  the  mucous  surfaces  of  the  mouth 
are  the  excretory,  or  discharging  ducts  or  tubes  of 
three  pairs  of  salivary  glands  —  the  parotid,  the  sub- 
maxillary, and  the  sub-lingual.  The  parotid  glands 
(so  named  from  two  Greek  words  signifying  "  ear " 
and  ^^near" — near  the  ear)  are  the  largest  of  the 
three  pairs,  weighing  from  a  half  ounce  to  an  ounce 
each.  They  are  situated  upon  the  sides  of  the  face 
immediately  below  and  in  front  of  the  external  ear. 
Their  ducts  lead  to  outlets,  which  can  usually  be  readily 
seen,  upon  the  inner  surfaces  of  the  cheeks  opposite 
the  second  molar  teeth  of  the  upper  jaw.  The  glands 
called  submaxillary  {beneath  the  jaw)  are  situated 
below  the  lower  jaw,  and  have  their  outlets  on  either 
side  of  the  middle  line  beneath  the  tongue.  The 
glands  called  sublingual  {beneath  the  torigue)  are 
situated  beneath  the  mucous  membrane  of  the  floor 
of  the  mouth,  their  ducts  —  from  eight  to  twenty  in 
number  —  opening  under  the  tongue. 

The  secretions  or  products  of  the  mucous  and  sali- 
vary glands  differ  in  character  as  do  those  of  the  latter 
from  one  another.  They  differ  also  in  the  quantity 
of  fluid  which  they  discharge,  and  as  to  the  causes 
which  excite  their  action.  The  parotids  are  called 
the  masticatory  glands,  because  they  are  not  found 
generally  except  in  animals  which  are  furnished  with 
2*  B 


1 8  THE   MOUTH  AND    THE    TEETH, 

grinding  or  masticating  teeth.  A  larger  quantity 
of  secretion  takes  place  from  them  than  from  either 
of  the  other  salivary  glands,  especially  during  the 
movements  of  the  jaw  in  eating,  and  particularly 
on  that  side  of  the  mouth  on  which  the  chewing  is 
being  done.  When  thus  stimulated  to  action  they 
pour  out  an  abundant  secretion,  which  becomes  in- 
corporated with  the  food  during  mastication,  uniting 
dry  particles  into  a  coherent  mass.  These  glands  are 
also  active  during  the  movements  of  the  jaw  caused 
by  continuous  speaking.  The  parotid  gland  is  the 
seat  of  the  inflammation  in  the  disease  called  mumps. 
The  submaxillary  glands  are  more  immediately  con- 
cerned in  the  sense  of  taste.  They  are  found  only 
in  those  animals  which  subsist  on  food  which  ap- 
peals to  that  sense,  being  almost  entirely  absent  in 
the  grain-eating  birds.  They  are  excited  to  special 
activity  by  the  introduction  into  the  mouth  of  sapid 
(tasteful)  substances.  The  sublingual  glands  are  par- 
ticularly stimulated  by  the  act  of  swallowing. 

The  secretion  from  the  parotid  glands  is  a  clear  and 
limpid  fluid ;  that  from  the  submaxillary  glands  is 
clear,  but  thick  and  viscid ;  that  from  the  sublingual 
is  thick,  glutinous,  and  ropy.  All  are  slightly  alka- 
line. 

The  function  of  the  parotid  glands  is  supposed  to 
be  to  moisten  the  food,  and  thus,  by  the  aid  of 
mastication,  to  give  it  the  requisite  consistency  and  . 


THE  MOUTH.  I9 

Convert  it  into  a  homogeneous  mass ;  that  of  the 
submaxillary,  to  promote  the  solution  of  soluble  sub- 
stances, in  order  that  they  may  make  an  impression 
upon  the  nerves  of  taste ;  that  of  the  sublingual,  to 
lubricate  the  food,  and  thus  facilitate  its  passage  into 
the  pharynx. 

The  secretion  of  the  mucous  glands  of  the  lips, 
cheeks,  gums,  tongue,  floor  and  roof  of  the  mouth,  is 
a  more  or  less  viscid,  transparent,  or  somewhat  turbid 
fluid,  generally  slightly  acid. 

These  different  and  distinct  secretions  all  unite  to 
form  the  fluid  ordinarily  termed  saliva.  This  mixed 
fluid  is  in  health  inodorous,  insipid,  slightly  viscid, 
and  generally  alkaline,  but  so  slightly  as  to  be  de- 
tected only  by  chemical  tests ;  it  is  composed  of 
water  holding  animal  and  various  earthy  matters  in 
solution.  It  is  this  mixed  fluid  by  which  the  cavity 
of  the  mouth  is  kept  constantly  moistened  —  a  neces- 
sity, if  for  nothing  else,  that  the  parts  may  be  in 
proper  condition  for  the  purposes  of  speech.  Another 
important  office  of  the  saliva  is  its  dissolving  effect 
upon  soluble  substances  introduced  into  the  mouth, 
thus  bringing  them  into  contact  with  the  nerves  of 
taste,  which  is  essential  to  the  enjoyment  of  food. 
It  also  lubricates  the  surfaces  of  the  mouth  and  teeth, 
and  thus  prevents  the  adhesion  of  food  to  them.  In 
consequence  of  its  glutinous  and  frothy  character,  it 
imprisons  innumerable  globules  of  air  along  with  the 


20  THE   MOUTH  AND    THE    TEETH. 

food  with  which  it  becomes  mixed,  thus  tending 
greatly  to  favor  the  subsequent  solution  of  the  latter 
by  the  fluids  of  the  stomach.  It  also  coats  the  masses 
of  food  when  ready  for  swallowing,  thus  favoring  their 
easy  transmission  to  the  stomach.  To  these  varied 
offices  must  be  added  another  —  a  certain  chemical 
effect  upon  the  food  (changing  starch  and  cane  or 
crystallizable  sugar  into  grape  or  uncrystallizable 
sugar),  which  is  the  first  step  in  the  series  of  chem- 
ical processes  (digestion)  by  which  the  food  is  pre- 
pared for  the  uses  of  the  economy.  That  the  action 
of  the  saliva  upon  starchy  foods  is  of  great  importance 
becomes  apparent  when  it  is  understood  that  starch 
as  such  is  insoluble,  and  would  therefore  be  not  only 
valueless  as  nutriment,  but  a  positive  burden  in  the 
alimentary  tract,  while  the  sugar  into  which  it  is  con- 
verted by  the  saliva  is  readily  soluble  and  nutritious. 
Still  another,  and  a  curious  as  well  as  important,  result 
of  the  slight  but  constant  discharge  from  the  mucous 
and  salivary  glands,  is  its  direct  influence  upon  the 
sense  of  hearing.  Its  presence,  even  when  unnoticed 
and  during  sleep,  causes  the  act  of  swallowing  at  short 
intervals,  which  effects  the  opening  of  the  Eustachian 
tube  (a  passage  leading  from  the  ear  to  the  throat) 
and  permits  the  renewal  of  air  in  the  cavity  of  the 
middle  ear— a  condition  essential  to  the  maintenance 
of  perfect  hearing.  A  most  interesting  provision  is 
shown  in  the  fact  that  a  nerve  (the  chorda  tympani), 


THE  MOUTH.  21 

whose  function  it  is  to  excite  the  secretion  of  saliva, 
passes  through  the  middle  ear,  and  thus  establishes 
a  direct  relation  between  the  sense  of  hearing  and 
the  salivary  glands,  so  that  certain  discordant  sounds 
cause  an  abundant  secretion  of  saliva,  the  swallow- 
ing of  which  serves  by  the  constant  renewal  of  air 
to  protect  the  ear  from  irritation,  as  before  explained. 
As  a  result  of  other  curious  nervous  connections,  the 
salivary  secretion,  so  essential,  as  has  been  shown, 
to  the  functions  of  speech  and  of  hearing,  is  also 
stimulated  by  the  sight,  smell,  or  even  the  thought  of 
savory  food.  The  quantity  of  saliva  discharged  into 
the  mouth  varies  with  the  condition  of  the  food  intro- 
duced, being  abundant  in  proportion  to  the  dryness 
of  the  food.  Its  secretion  varies,  also,  with  the  vary- 
ing health  of  the  body.  It  is  much  diminished  and 
sometimes  almost  suspended  by  fear,  anxiety,  or  other 
depressing  emotions.  In  diseased  conditions  of  the 
general  system  its  character  is  variously  modified, 
becoming  acid  or  excessively  alkaline ;  acting  upon 
the  soft  tissues  of  the  mouth,  causing  ulcerations  of 
the  mucous  membrane  and  recession  of  the  gums ; 
acting  upon  the  hard  tissues,  causing  their  disinte- 
gration. 

Diseased  conditions,  therefore,  of  the  general  sys- 
tem influence  unfavorably  the  health  of  the  mouth, 
and  notably  of  the  dental  organism.  In  febrile 
conditions    there    is    more    or   less   suppression    of 


22  THE   MOUTH  AND    THE    TEETH. 

the  secretions  of  the  salivary  glands,  and  often  a 
greatly  increased  and  vitiated  secretion  from  the  mu- 
cous glands,  which  because  of  its  viscidity  collects 
and  thickens  about  the  teeth,  entangling  with  it  vari- 
ous extraneous  matters  and  d3ris  found  in  the  mouth, 
its  accumulation  being  favored  by  the  fact  that  during 
illness  the  usual  cleansing  of  the  mouth  and  teeth  by 
thorough  rinsing  and  the  brush  is  neglected ;  and,  as 
ordinarily  at  such  times  there  is  but  slight  demand  for 
food,  and  especially  for  food  requiring  mastication, 
the  deposit  is  left  undisturbed  and  soon  undergoes 
fermentation,  becoming  strongly  acid.  Thus  it  often 
happens  that  during  a  severe  illness  very  serious  in- 
roads are  made  upon  the  integrity  of  the  structures 
of  the  teeth,  which  are  attributed  frequently  and 
erroneously  to  the  medicine  taken.  It  follows,  there- 
fore, that  during  sickness  these  untoward  influences 
should  be  combated  with  more  than  ordinary  care. 
Such  care  is  suggested  not  only  by  the  rapidly  de- 
structive effects  of  the  vitiated  salivary  and  mucous 
secretions  upon  the  teeth,  but  by  the  vicious  circle 
thus  established  ;  the  products  of  the  deranged  action 
of  these  glands  not  only  creating  local  mischief, 
but  causing  an  irritation  of  the  mucous  membrane  of 
the  alimentary  tract,  and  by  this  means,  as  well  as  by 
their  presence,  resulting  in  an  impairment  of  the  di- 
gestive fluids.  The  exhalations  from  a  diseased  mouth 
may  also  produce  an  injurious  eff'ect  upon  the  bron- 


THE  MOUTH.  2$ 

chial  tubes  and  lungs,  and  through  them  upon  the 
blood. 

Sometimes,  and  owing  to  various  causes,  such  as 
wounds,  burns,  abscesses,  or  dead  and  ulcerated  roots 
remaining  in  the  mouth,  the  continuity  of  the  ducts 
or  tubes  of  the  salivary  glands  is  destroyed,  and  false 
openings  upon  the  cheek,  chin,  or  throat  result.  In 
such  cases  the  secretion  is  discharged  through  the 
false  opening,  and  poured  over  the  external  parts. 
Sometimes  also,  from  similar  or  other  causes,  these 
ducts  become  obstructed,  in  which  case  the  secretion, 
continuing  and  finding  no  means  of  escape,  distends 
the  tissues,  and  forms  a  soft  tumor  called  a  ''ranula," 
generally  upon  the  lip,  or  upon  the  floor  of  the  mouth 
beneath  the  tongue.  Such  conditions  require,  of 
course,  surgical  interference  for  their  cure. 

The  gum  is  a  thin,  compact,  tough,  elastci,  fibrous 
tissue  enveloping  the  alveolar  processes,  and  surround- 
ing the  teeth  at  their  necks.  It  is  continuous  with 
the  mucous  membrane  which  lines  the  inside  of  the 
lips  and  cheeks  and  the  floor  and  roof  of  the  mouth, 
and  at  the  necks  of  the  teeth  with  the  membrane 
(called  the  pericemcnticm)  which  lines  their  sockets 
and  also  invests  their  roots.  In  a  healthy  condition 
the  gum  has  comparatively  little  sensibility,  bearing 
without  irritation  the  friction  to  which  it  is  subjected 
in  mastication.  This  insensibility  is  also  evidenced 
by  the  immunity  from  pain  when  the  gums  are  used 


24 


THE   MOUTH  AND    THE    TEETH. 


in  chewing,  by  the  child  before  the  eruption  of  teetli 

and  by  those  wlio  have  suffered  the  loss  of  their  teeth. 

Fig.  I.  shows    one-half    of   the  upper   jaw.      The 

upper  jaw  —  called  the  sii- 
perior  inaxilla  —  is  formed 
by  two  bones  united  in  the 
central,  or  median,  line  of 
the  face.  Each  of  these 
bones  contributes  to  the  for- 
mation of  three  cavities  — 
the  roof  of  the  mouth,  the 
outer  wall  and  floor  of  the 
nose,  and  the  floor  of  the 
socket  (the  orbit)  of  the  eye. 
Each  upper  jawbone  has 
a  triangular  -  shaped  cavity 
called  the  antrum  (a  cave) ;  the  floor  of  which  is 
sometimes  perforated  by  the  roots  of  the  teeth  if  they 
are  unusually  long.  The  upper  jaw  is  tightly  wedged 
in  by  the  outer  bones  of  the  face,  and  has  no  power 
of  motion  —  the  teeth  of  the  upper  jaw  presenting  a 
fixed  surface,  against  which  those  of  the  lower  are 
brought  to  bear  in  mastication.  That  part  of  the 
upper  jaw  which  carries  the  incisor  teeth  has  a  sepa- 
rate centre  of  development,  and  in  early  intra-uterine 
life  in  man  is  a  separate  bone  called  the  "incisive" 
or  "intermaxillary"  bone.  It  remains  a  separate 
bone  in  most  adult  mammals,  but  is  generally  closed 


THE   MOUTH. 


25 


in  man.  Occasionally  the  fissure  between  this  bone 
and  the  upper  jaw  is  not  closed  on  one  side  or  both. 
This  deformity  is  called  "cleft-palate."  When  the 
fissure  is  in  the  lip  only,  it  is  called  '•'  hare-lip,"  from 
its  resemblance  to  the  grooved  lip  of  the  hare.  The 
anatomical  development  explains  why  this  is  never  in 
the  middle  line,  but  always  on  one  side,  or  in  case  of 
''double  hare-lip"  on  both.  Hare-lip  often  exists 
alone,  but  where  the  palate  is  cleft  the  lip  is  apt  to 
be  so  too,  though  this  is  not  always  the  case. 

The   lower  jaw  —  called   the  itiferior  maxilla,  or 
mandible  (shown  in   Fig.   11.) — is  the  largest   and 
strongest  bone  of  the  face.    It  consists  of  a  curved  hor- 
izontal portion  (the 
body),  and  two  up- 
right portions  called 
the   rami   (singular, 
ramus  —  a  branch). 
In  infancy  these  up- 
right portions  form 
an  obtuse  angle  with 
the  horizontal   por- 
tion ;   in  the  adult, 
almost  a  right  angle, 

the  angle  becoming  again  obtuse  in  old  age. 
these  modifications  in  the  lower  jaw  which  to  a  large 
degree  give  the  characteristic  forms  to  the  face  in  in- 
fancy, in  maturity,  and  in  old  age.  Fig.  III.  shows  the 
3 


Fig.  II. 


It  is 


26 


THE   MOUTH  AND    THE    TEETH. 


relative  forms  of  the  lower  jaw  at  these  three  periods 
of  life.  A  canal  of  considerable  size  runs  through  the 
body  of  the  lower  jaw,  giving  space  for  the  passage  of 

blood-vessels       and 


nerves  for  the  sup- 
ply of  the  teeth. 
These  pass  out 
through  openings 
beneath  the  bicus- 
pid teeth  on  either 
side  (shown  in  Fig. 
III.),  and  are  dis- 
tributed to  the  chin, 
1  wer  lip,  and  gum 
/  of  the  lower  jaw. 
The  closure  of  the 
jaws  is  effected  by 
f  ur  pairs  of  strong 
luuscles  —  two  at- 
tached to  the  outer 
and  two  to  the  inner 


Fig.  III. 


side  of  the  rami  of  the  lower  jaw.  The  peculiar  ar- 
ticulation or  jointing  of  the  lower  jaw  in  man  allows 
of  a  great  variety  of  movements,  in  keeping  with  the 
diversified  character  of  his  food,  as  well  as  with  other 
and  varied  uses. 

The  alveolar  processes  consist  of  two  plates  of  bone, 
an  outer  and  an  inner,  forming  borders  to  the  jaws 


THE  MOUTH. 


27 


and  supports  to  the  gums.     These  are  connected  by 
transverse  plates,  dividing  the  space  into  numerous 
cavities  which  form  the  sockets  of  the  teeth.     An 
upper  jaw  from  which  the  teeth  have   been  recently 
extracted    is    il- 
lustrated in  Fig. 
IV.     The  edges 
of  the    alveolar 
processes        dip 
down      between 
the  teeth,  so  that 
their        margin 
presents     a    fes- 
tooned   appear- 
ance.     At     the 
bottom  of  each  socket  there  is  an  opening  to  admit 
the  passage  of  the  blood-vessels  and  nerves  of  the 
teeth.     After  the  loss  of  the  teeth  the  alveolar  pro- 
cesses are  absorbed  and  disappear ;  so  that  the  roof 
of  the  mouth  generally  loses  its  arched  appearance 
and  becomes  nearly  flat,  and  the  lower  jaw  assumes 
the  peculiar  form   characteristic  of  old  age.     When 
the  processes  are  carious  or  have  been  absorbed,   the 
teeth  become  loose  and  have  to  be  removed. 

The  pericementum  is  a  tough,  fibrous  tissue  which 
invests  the  roots  of  the  teeth  and  lines  their  sockets. 
The  cementum  or  outer  layer  of  the  roots  receives 
its  nourishment  through  it.      It  is  owing  to  this  fact 


Fig.  IV. 


28  THE  MOUTH  AND    THE    TEETH, 

that  after  the  death  of  its  pulp  a  tooth  still  possesses 
a  certain  amount  of  vitality,  and  is  therefore  re- 
tained in  its  socket,  —  frequently  for  years, —  which 
would  not  be  the  case  if  it  did  not  hold  a  vital  rela- 
tion to  the  jaw.  The  pericementum,  moreover,  while 
attaching  the  teeth  firmly  to  their  sockets,  serves  as  an 
elastic  pad  or  cushion,  preventing  to  a  considerable 
extent  the  damaging  effects  upon  the  teeth  which 
would  otherwise  be  experienced  from  accidental  blows 
or  other  violence,  as  well  as  from  the  thoughtless  and 
unnecessary  voluntary  injury  by  efforts  to  crack  nuts, 
untie  knots,  and  other  like  foolish  procedures. 

The  movements  of  the  masticatory  apparatus  of  the 
human  being  are  more  complex  and  more  varied  than 
of  any  other  animal,  resembling  those  of  both  the 
flesh-eating  and  grazing  species,  showing,  as  does 
also  the  comparative  anatomy  of  the  teeth,  that  the 
human  race  is  adapted  to  live  on  a  mixed  diet. 
The  process  of  mastication,  which  is  one  of  very  great 
importance,  consists  in  dividing  and  comminuting 
the  food  by  the  teeth,  reducing  it  to  a  state  of  com- 
plete disintegration,  which  is  a  necessary  condition 
for  its  insalivation  —  the  mixture  of  the  food  with  the 
fluids  of  the  mouth  —  and  subsequently  for  the  action 
of  the  digestive  fluids  of  the  intestinal  tract.  Food 
is  more  or  less  easily  digested  in  proportion  as  it  has 
undergone  thorough  mastication.  To  appreciate  this 
fact,  it  must  be  remembered  that  stomach  digestion 


THE    MOUTH. 


29 


is  chiefly  chemical.  It  will,  therefore,  be  readily  un- 
derstood that  the  more  finely  the  food  is  divided 
before  it  is  brought  into  contact  with  the  digestive 
fluids,  the  larger  will  be  the  surface  exposed  to  their 
action,  and  consequently  the  more  easily  will  it  be  at- 
tacked and  the  more  speedily  will  it  be  dissolved,  just 
as  any  solid  is  more  readily  dissolved  if  first  ground 
to  a  powder.  It  is  not  easy  to  overrate  the  importance 
to  the  digestive  process  of  a  thorough  preliminary 
mastication.  Masses  of  food  introduced  into  the 
stomach  may  remain  for  a  long  time  —  days,  even 
weeks  —  undissolved,  disturbing  its  functions  and 
undergoing  fermentative  and  putrefactive  changes, 
caused  by  warmth  and  moisture,  creating  gases  and 
acids,  and,  if  not  expelled  by  vomiting,  becoming  a 
source  of  irritation  and  disturbance  in  its  course 
throughout  the  whole  length  of  the  intestinal  tract. 
In  fact,  if  mastication  is  not  properly  performed, 
the  subsequent  process  of  digestion  is  likely  to  be 
deranged.  There  is  no  more  common  cause  of  indi- 
gestion or  dyspepsia  than  imperfect  mastication  ;  no 
more  fruitful  source  of  headache,  neuralgia,  nausea, 
heartburn,  flatulence,  cramp,  diarrhea,  dysentery,  and 
various  other  disorders.  Indigestion,  largely  induced 
by  imperfect  mastication,  is  the  prevailing  malady 
of  civilized  life  —  probably  the  occasion  of  more  dis- 
orders than  can  be  traced  to  any  other  one  cause. 
The  result  is,  of  course,  the  same,  whether  the  fault 
3* 


30  THE   MOUTH  AND    THE    TEETH. 

lies  in  the  haste  with  which  the  food  is  swallowed 
without  proper  mastication,  or  whether  the  mastica- 
tory apparatus  be  defective.  There  is  no  question  that 
in  many  cases  an  increase  of  longevity  is  fairly  at- 
tributable to  the  improved  facilities  for  mastication 
secured  by  proper  attention  to  the  natural  teeth,  or  in 
case  of  their  loss  by  the  use  of  artificial  teeth.  It 
should  be  remembered  that  when,  owing  to  imperfect 
mastication,  the  food  is  passed  into  the  stomach  in  a 
crude  state,  and  therefore  unfit  for  digestion,  the  teeth 
themselves  suffer  by  reason  of  the  resulting  vitiation 
of  the  digestive  fluids,  which  by  regurgitation  exercise 
an  injurious  influence  upon  tooth -structure.  Another 
argument  in  favor  of  thorough  mastication  is  to  be 
found  in  its  directly  beneficial  effects  upon  the  teeth ; 
for,  although  these  organs  serve  the  purposes  of  vo- 
calization, ornamentation,  etc.,  there  can  be  no  doubt 
that  their  chief  office  is  the  mastication  of  food. 
Neither  can  there  be  any  doubt  that  the  neglect  to 
exercise  this  special  function  impairs  their  vitality, 
as  the  disuse  of  any  organ,  sense,  or  structare  of  the 
body  results  in  its  degeneration  and  gradual  loss  of 
power.  A  tooth  having  lost  its  antagonist  —  that  is, 
the  tooth  which  opposed  it  in  mastication  —  will  gen- 
erally elongate  or  rise  beyond  the  line  of  its  fellows, 
as  though  in  search  of  an  opposing  force  ;  from  which 
it  appears  that  the  pressure  exerted  upon  the  teeth 
during  use  in  mastication  is  essential  to  their  retention 


THE   MOUTH.  3  I 

in  a  healthy  condition  in  the  jaws.  The  teeth  are 
strengthened  in  their  attachments  and  in  their  vital 
relations  to  the  jaws  by  exercise.  There  is,  therefore, 
in  the  case  of  teeth  not  properly  exercised,  a  lessened 
nutritive  supply,  both  through  the  pulp  and  through 
the  membrane  which  gives  vitality  to  the  roots. 
Nor  can  the  use  of  the  brush  and  powder  compen- 
sate for  the  important  service  which  the  habitual, 
thorough  mastication  of  food  accomplishes  in  secur- 
ing cleanliness  of  the  surfaces  of  the  teeth  ;  the  tritu- 
ration of  food  effecting  that  which  one  is  utterly 
unable  to  do  with  the  brush.  In  addition  to  the  of- 
fices of  the  teeth  in  ornamentation,  in  their  mechan- 
ical functions,  in  their  relation  to  the  articulation 
and- modulation  of  sound,  they  serve  another  and 
important  purpose  as  conservators  of  the  lungs  and 
the  organs  of  voice,  preventing  the  breath  in  the  act 
of  speaking  from  being  exhausted  too  rapidly.  Per- 
sons who  have  lost  their  teeth  find  continued  speak- 
ing, as  in  conversation,  difficult,  because  each  utter- 
ance empties  the  mouth  of  air,  and  more  rapid 
breathing  is  required  to  keep  up  the  supply.  This 
effort  soon  becomes  fatiguing  ;  causes  a  feeling  of 
weakness  and  distress,  and  is  apt  to  produce  an  irrita- 
tion of  the  larynx  and  a  chronic  cough.  The  cough 
in  turn  increases  the  irritation,  and  thus  a  vicious 
circle  is  established  which  may  involve  the  bron- 
chial tubes  and  the  lungs,  and  result  in  serious  dis- 
comfort and  even  in  dangerous  complications. 


CHAPTER   III. 

ANATOMY    OF   THE   TEETH. 

THE  animal  kingdom  exhibits  a  wonderful  diver- 
sity in  the  dental  structures  of  its  various  classes, 
corresponding  to  an  equal  diversity  in  the  uses  re- 
quired of  them  by  the  instincts  and  necessities  of 
the  animal.  Their  conformation  indicates  so  defi- 
nitely the  species  in  which  they  are  found  that  they 
are  accepted  as  one  of  the  best  means  of  classifica- 
tion, showing  the  distinguishing  peculiarities  of  the 
animals  to  which  they  respectively  belong. 

The  teeth  in  man  are  hard,  bone-like  structures 
implanted  in  sockets  along  the  jaws,  and  are  in- 
tended to  fulfil  various  useful  purposes.  Two  sets  of 
teeth  are  developed  in  the  human  mouth  —  the  first 
called  the  deciduous,  temporary,  or  milk  teeth;  the 
second,  the  permanent  set. 

A  tooth  consists  of  enamel,  cementum,  dentine,  and 

dental  pulp.     The  exposed  part  —  that  above  the  gum 

—  is  called  the  croivn  ;  that  wliich  is  held  within  the 

socket,  the  root ;  and  the  narrow  part  between  the 

crown  and  the  root,  the  neck. 

32 


ANATOMY  OF   THE    TEETH.  33 

The  enamel  is  the  cap  or  covering  of  the  crown. 
It  is  the  hardest  tissue  of  the  body.  It  is  thickest 
on  the  cutting  edges  and  masticating  surfaces,  gradu- 
ally becoming  thinner  towards  the  neck,  at  which 
point  it  is  met  or  slightly  overlapped  by  the  cementum. 
The  enamel  is  possessed  of  very  slight  if 
of  any  sensibility.  It  contains  not  more  \ 
than  four  per  cent,  of  animal  matter,  and 
is  almost  entirely  soluble  in  acids.  Under 
the  microscope  it  is  found  to  consist  of 
parallel  fibres  or  rods  lying  side  by  side  ^^§^'  ^' 
—  generally  hexagonal,  but  some  nearly  circular,  and 
others  nearly  square.  A  transverse  section  of  enamel 
fibres  is  shown  in  Fig.  V. 

The  cementum  is  a  layer  of  hard  tissue  covering  the 
roots  of  the  teeth.  It  is  intermediate  in  hardness 
between  dentine  and  bone,  resembling  the  latter  more 
than  either  of  the  other  hard  tissues  found  in  a  tooth. 
It  is  thickest  at  the  terminus  of  the  root,  gradually 
diminishing  until  it  seems  to  unite  with  or  slightly 
overlap  the  enamel  at  the  neck  of  the  tooth. 

The  dentine,  or  so-called  ivory,  constitutes  the  bulk 
of  the  tooth.  It  is,  so  to  speak,  its  framework,  giving 
each  tooth  its  size  and  shape.  If  the  enamel  and 
cementum  were  removed,  the  dentine  would  still  pre- 
serve the  general  form  of  the  tooth.  It  is  commonly 
but  erroneously  called  tooth-bone.  It  contains  over 
one-fourth  of  animal  matter,  and  when  subjected  to 

C 


34  THE  MOUTH  AND    THE    TEETH. 

the  action  of  acids  the  earthy  matter  is  dissolved  out, 
leaving  a  cartilage-like  mass  retaining  the  form  of  the 
tooth.  Examined  microscopically,  it  is  found  to  con- 
sist of  innumerable  tubes  of  a  diameter  of  about  45^0 
of  an  inch.  It  is  usually  highly  sensitive  both  to 
variations  of  temperature  and  to  contact  with  foreign 
substances,  making  the  excavation  of  a  cavity  in  a 
tooth,  preparatory  to  filling,  more  or  less  painful.  It 
is  more  sensitive  just  beneath  the  enamel  than  in  its 
deeper  portions.  It  owes  nearly  all  its  sensitiveness, 
however,  to  the  pulp  of  the  tooth,  and  when  the  pulp 
dies  the  dentine  loses  almost  all,  if  not  all,  of  its 
sensibility. 

The  pulp,  commonly  but  incorrectly  called  the 
nerve,  occupies  a  cavity  in  the  centre  of  the  tooth  and 
corresponds  to  its  general  form.  This  pulp  is  the 
uncalcified  portion  of  the  original  germ  of  the  tooth. 
From  this  the  dentine  was  developed,  the  pulp  being 
gradually  converted  into  that  substance  up  to  a  certain 
point,  when  the  process  of  calcification  or  deposit  of 
earthy  matter  ceased,  leaving  a  cavity  occupied  by 
what  was  left  of  the  pulp.  The  pulp  is  a  mass  com- 
posed of  nerves  and  blood-vessels  held  together  by 
a  cobweb-like  connective  tissue.  It  is  acutely  sensi- 
tive not  only  to  contact  with  foreign  substances,  but 
to  variations  of  temperature.  The  pulp  supplies  nour- 
ishment to  the  tooth.  When  it  dies  the  tooth  loses 
its  translucency,  the  dentine  loses  its  sensibility  and 


ANATOMY  OF  THE    TEETH. 


35 


gradually  changes  in  color.  Nerves  and  blood-vessels 
enter  through  the  minute  opening  at  the  extremity  of 
the  root,  and  pass  through  the  small  canal  in  the  root 
to  the  pulp  cavity.  With  the  exception  of  this  small 
aperture,  the  pulp  is  entirely  surrounded  by  solid  den- 


Fig.  VI.  Fig.  VII.  Fig.  VIII. 

tine.  Figs.  VI.  and  VII.  represent  a  central  incisor 
and  a  molar,  split  vertically  so  as  to  show  their  various 
parts.  A  is  the  cutting  edge  or  grinding  surface, 
covered,  as  is  the  entire  crown,  with  enamel ;  B, 
the  cementum  covering  the  roots ;  C,  the  dentine ; 
D,  the  pulp  cavity.  Fig.  VIII.  shows  a  transverse 
section  of  a  molar,  of  natural  size,  in  which  i  is  the 
dentine  ;   2,  the  enamel ;  3,  the  pulp  cavity. 

The  teeth  do  not  change  in  shape  or  increase  in 
size  after  they  are  erupted,  though  their  tissues  gradu- 
ally become  denser  and  harder.  The  crowns  are 
completed  as  to  size  and  form  before  their  eruption. 
The  roots,  however,  are  not  completed  at  that  time, 
and,  instead  of  a  conical  termination  with  a  minute 


36  THE  MOUTH  AND    THE    TEETH. 

opening  at  the  end  of  the  root,  the  aperture  is  quite 
large.  The  enamel,  which  when  fully  hardened  will 
strike  sparks  with  steel,  is  still  comparatively  soft. 
It  undergoes  a  gradual  process  of  hardening  after  the 
eruption  of  the  tooth;  but  this  is  the  only  change 
except  that  of  decay  —  for,  although  it  contains  a 
small  proportion  of  animal  matter,  and  is  therefore 
of  necessity  nourished,  there  is  not  a  sufficient  nutri- 
tive supply  for  its  repair  or  renewal,  and  consequently 
when  once  destroyed,  either  by  disease  or  accident, 
it  cannot  be  restored. 

Classification  of  the  Teeth. — The  permanent 
set  of  teeth  consists  of  thirty-two  —  sixteen  in  each 
jaw.  Those  in  the  upper  jaw  are  called  the  supe- 
rior; those  in  the  lower,  the  inferior.  They  are 
divided  into  four  classes,  viz.,  incisors,  cuspids,  bi- 
cuspids, and  molars.  Fig.  IX.  represents  the  per- 
manent teeth  —  superior  and  inferior  —  of  the  left 
side.  The  incisors  —  four  in  each  jaw  —  are  so  called 
from  the  Latin  word  incidere  (to  cut),  on  account  of 
their  sharp  edges.  This  class  is  subdivided  into  cen- 
tral incisors,  because  of  their  position  in  the  centre  of 
the  arch,  and  lateral  incisors,  because  they  stand  on 
either  side  of  the  centrals.  The  second  class  com- 
prises four  teeth  —  two  in  each  jaw — called  cuspids  or 
cuspidati  (singular,  cuspidatus),  from  the  Latin  word 
cuspis  (a  spear),  because  they  terminate  in  a  point. 
They  are  comrhonly  known  by  the  name  of  canines. 


ANATOMY  OF   THE    TEETH.  37 


Fig.  IX.  — Permanent  Teeth  of  the  Left  Side. 
4 


38  THE  MOUTH  AND    THE    TEETH, 

or  those  of  the  upper  jaw  as  eye  teeth,  and  those  of 
the  lower  jaw  as  stomach  teeth.  They  are  situated  on 
the  outer  side  of  each  lateral  incisor.  The  third  class 
comprises  eight  teeth  —  four  in  each  jaw — called  bi- 
cuspids or  bicuspidati  (singular,  bicuspidaius),  from 
the  Latin  words  bis  (twice)  and  cuspis  (a  spear)  — 
double-pointed.  They  are  sometimes  designated  as 
pre-molars  or  half-molars.  They  are  situated  imme- 
diately behind  the  cuspids,  holding  an  intermediate 
relation  to  them  and  the  molars,  and  are  known 
as  the  first  and  second  bicuspids.  The  fourth  class 
consists  of  twelve  teeth  —  six  in  each  jaw.  They  are 
called  molars  —  Latin,  molares  (singular,  7nolaris)  — 
from  molere  (to  grind,  as  in  a  mill).  They  are  situ- 
ated back  of  the  bicuspids,  and  are  known  as  the 
first,  second,  and  third  molars.  The  first,  because 
of  the  time  of  their  eruption,  are  called  the  sixth- 
year  molars ;  the  second,  for  the  same  reason,  are 
known  as  the  twelfth-year  molars ;  and  the  third,  for 
a  like  reason,  are  denominated  the  dentes  sapiential 
(singular,  dens  sapientiae),  or  wisdom  teeth  —  from 
the  Latin  words  dens  (a  tooth)  and  sapientia  (knowl- 
edge or  wisdom),  the  teeth  of  wisdom  —  because  they 
are  not  erupted  until  the  individual  has  reached  ma- 
turity. 

The  incisors  are  double-wedge  shape  —  widest  at 
the  cutting  edge,  thickest  at  the  neck,  slightly  con- 
cave on  the  inner  and  slightly  convex  on  the  outer 


ANATOMY  OF   THE    TEETH.  39 

surface.  The  superior  or  upper  are  larger  than  the 
inferior  or  lower  incisors,  and  the  central  incisors  are 
wider  than  the  lateral.  In  the  case  of  the  inferior 
incisors,  the  laterals  are  wider  than  the  centrals.  The 
incisors,  both  superior  and  inferior,  have  each  but  one 
root.  The  use  of  these  teeth  in  eating  is  to  ''  bite  " 
or  cut  off  a  portion  of  food,  operating  on  the  same 
principle  as  a  pair  of  scissors.  The  cuspids  are  less 
concave  on  the  inner  surface,  and  more  conv^ex  on  the 
outer  surface  than  the  incisors,  and  terminate  in  a 
point.  They  have  but  one  root,  but  this  is  longer 
and  stronger  than  that  of  any  other  tooth  in  the 
mouth.  The  superior  cuspids  are  larger  and  have 
longer  roots  than  the  inferior.  The  use  of  the  cuspids 
is  to  seize  and  tear  or  lacerate  obstinate  substances 
preparatory  to  mastication.  It  is  an  interesting  fact 
that  these  teeth  are  more  prominent  in  proportion 
as  the  animal  approaches  the  purely  carnivorous  or 
flesh-eating  class,  and  are  never  found  in  an  animal 
having  horns.  The  bicuspids  are  smaller  than  the 
cuspids,  convex  on  both  outer  and  inner  surfaces,  and 
flattened  on  the  sides.  Their  long  diameter  is  across 
the  jaw.  The  roots  are  conical.  Tlie  inferior  have 
but  one  root;  the  superior  sometimes  a  single  root, 
often  deeply  grooved,  and  sometimes  entirely  divided 
—  bifid.  The  molars  have  large  grinding  surfaces, 
divided  by  grooves  into  cusps  or  points.  The  crowns 
of  the  inferior  are  larger  than  those  of  the  superior. 


40  THE   MOUTH  AXD    THE    TEETH. 

In  each  jaw  they  decrease  in  size  from  before  back- 
ward. The  superior  first  and  second  molars  have  as  a 
rule  three  roots  each.  The  inferior  first  and  second 
molars  have  each  two  roots,  which  are  often  deeply 
grooved,  and  sometimes  bifid.  The  third  molars  or 
wisdom  teeth  of   both  jaws  have  but  a  single  root 


each,  though  this  is  sometimes  divided  into  three  in 
the  upper  jaw  and  two  in  the  lower.  The  inferior 
third  molar  is  larger  than  the  superior. 

The  deciduous  or  temporary  teeth  are  much  smaller 
than  the  permanent,  although  the  roots  are  generally 
larger  and  longer    in  proportion    to  the    size  of  the 


ANATOMY  OF   THE    TEETH.  4 1 

crowns  than  those  of  the  adult  set.  There  are  only- 
twenty  teeth  in  the  deciduous  set  — four  incisors,  two 
cuspids,  and  four  molars  in  each  jaw.  Fig.  X.  rep- 
resents the  temporary  teeth — superior  and  inferior  — 
of  the  left  side.  There  are  no  bicuspids  and  no  third 
molars  or  wisdom  teeth  in  the  temporary  set.  Four 
bicuspids  and  two  wisdom  teeth  in  each  jaw  —  twelve 
in  all  —  which  are  not  in  the  deciduous  or  temporary 
set,  make  the  permanent  set  to  consist  of  thirty-two 
teeth. 

The  surfaces  of  the  teeth  which  are  towards  the 
lips  are  called  "labial;  "  towards  the  cheeks,  "buc- 
cal; "  towards  the  tongue  on  the  lower  jaw,  "lin- 
gual," and  towards  the  roof  of  the  mouth  on  the 
upper  jaw,  "palatal."  The  surfaces  next  to  each 
other  are  called  "  proximate ;  "  those  looking  towards 
the  centre,  "mesial,"  and  those  looking  from  the 
centre,  "distal."  The  parts  of  the  six  front  teeth 
of  both  jaws  which  come  in  contact  with  each  other 
are  called  the  "cutting  edges,"  and  the  broad  sur- 
faces of  the  bicuspids  and  molars  which  are  brought 
in  contact  in  the  act  of  masticating  are  called  the 
"grinding  or  articulating  surfaces." 

Arrangement  of  the  Teeth. — The  teeth  in  man 
are  arranged  in  close  contact,  without  intervening 
spaces,  affording  each  other  mutual  support  after  the 
manner  of  staves  in  a  barrel.  Being  set  without  in- 
terspaces on  a  curved  line,  it  follows  that  their  outer 
4* 


42  THE   MOUTH  AND    THE    TEETH. 

surfaces  are  wider  than  the  inner.  The  upper  arch 
is  larger  than  the  lower,  and  from  this  fact  the  in- 
cisors and  cuspids  of  the  upper  jaw,  when  the  mouth 
is  closed,  overhang  or  shut  in  front  of  the  lower  teeth. 
The  upper  central  incisors  are  broader  than  the  lower, 
during   occlusion  causing  the  teeth  on  either   side 


of  them  to  be  thrown  out  of  exact  correspondence 
with  those  of  the  lower  jaw  occupying  the  same  rela- 
tive positions,  thus  bringing  about  an  irregularity  of 
opposition,  like  that  called  by  bricklayers  "breaking 
joints"  — so  that  each  tooth,  instead  of  being  antag- 
onized by  a  single  tooth,  is  met  by  portions  of  the 


ANATOMY  OF  THE    TEETH.  43 

surfaces  of  two  teeth,  as  illustrated  in  Fig.  XI,  Further 
back  in  the  arch  the  difference  is  harmonized  by  an 
increase  in  the  size  of  the  molars  of  the  lower  jaw 
beyond  that  of  the  upper,  which  brings  the  arches  out 
even.  This  irregularity  of  opposition  of  the  upper 
and  lower  sets  is  a  valuable  feature,  as  when  a  tooth 
is  lost  from  the  arch  in  either  jaw  the  opposing  tooth 
is  not  rendered  useless,  as  it  would  be  if  the  teeth 
were  in  perfect  opposition  with  one  another,  because 
it  is  brought  at  least  partially  into  contact,  during 
mastication,  with  the  tooth  which  adjoined  the  miss- 
ing one. 

In  rabbits  and  other  ''Rodents"  the  teeth  grow 
constantly  in  length,  in  order  to  repair  the  waste  due 
to  their  use  in  gnawing.  A  curious  result  follows  the 
loss  of  one  of  the  incisor  teeth  in  these  animals. 
The  opposite  remaining  tooth  not  being  worn  away, 
grows  to  such  a  length  as  to  prevent  gnawing,  and  so 
causes  the  death  of  the  animal  by  starvation. 


CHAPTER   IV. 

DEVELOPiMENT    OF   THE   TEETH. 

THE  development  of  the  teeth  is  one  of  the  most 
curious  and  interesting  of  the  processes  of  growth 
in  the  body.  At  about  the  seventh  week  of  fetal  life, 
small  gelatinous  bodies,  which  are  the  tooth  pulps,  are 
distinguishable  in  the  jaws  ;  and  at  about  the  tenth 
week  the  germs  or  developing  pulps  of  all  the  tem- 
porary teeth  —  twenty  in  number  —  are  in  position. 
These  germs  gradually  increase  in  size,  assuming  the 
shapes  of  the  teeth  which  they  are  to  form.  Mean- 
while, the  enamel  and  the  cementum  are  being  formed, 
each  from  a  separate  matrix  or  mother:  the  alveolar 
processes  are  being  built  along  and  across  the  jaws, 
dividing  the  pulp  of  each  tooth  from  its  fellow,  and 
providing  a  separate  socket  for  each  root,  so  that 
when  matured  they  will  afford  firm  support  to  the 
teeth.  At  the  same  time,  the  different  membranes 
which  are  to  line  the  sockets  and  cover  the  roots  of 
the  future  teeth,  those  which  are  to  cover  the  jaw- 
bones, and  those  to  cover  the  gums  externally,  are 
also  developing. 

44 


DEVELOPMENT   OF   THE    TEETH.  45 

When  the  pulps  have  attained  proper  dimensions, 
representing  the  forms  of  the  future  teeth,  they  are 
gradually,  by  a  process  known  as  calcification,  par- 
tially converted  into  the  dentine,  which  forms  the 
largest  portion  of  the  bulk  of  each  tooth ;  the  enamel 
which  is  to  protect  the  crowns  and  the  cementum  to 
cover  the  roots  continuing  to  be  deposited.  At 
birth  the  forms  of  the  crowns  have  been  fully  de- 
veloped, though  the  roots  are  as  yet  but  partially 
formed  ;  these  latter  being  the  result  of  the  elongation 
of  the  pulps  and  the  deposit  of  dentine  and  cementum. 
The  alveolar  processes  are  gradually  built  up,  and, 
after  they  have  reached  a  sufficient  height  above  the 
crowns  of  the  teeth,  their  edges  approximate  so  as 
to  partially  close  them  in  and  form  bony  cells,  within 
which  the  further  development  of  the  teeth  is  con- 
tinued. 

During  the  development  of  the  deciduous  or  tem- 
porary teeth  there  appears,  at  about  the  fourth  month  of 
fetal  life,  a  second  set  of  little  gelatinous  bodies,  which 
are  the  germs  of  the  second  or  permanent  teeth.  Of 
these,  first  in  order  of  appearance  are  those  of  the 
first  or  sixth-year  molars  (to  be  erupted  when  the  child 
is  about  six  years  of  age) ;  next,  those  of  the  central 
and  lateral  incisors  (to  be  erupted  at  about  the  eighth 
year  of  age) ;  then  those  of  the  cuspids  (canines  or 
eye  teeth)  ;  then  the  first  and  the  second  half-molars 
(bicuspids).     Thus,  at  birth  we  find  in  the  jaws  the 


46  THE   MOUTH  AND    THE    TEETH. 

twenty  deciduous  or  temporary  teeth  all  in  a  state  of 
forwardness,  and  also  the  germs  of  twenty-four  of  the 
permanent  set  in  various  stages  of  development.  The 
germs  of  the  second  or  twelfth-year  molars  do  not 
make  their  appearance  until  three  months  after  birth, 
and  those  of  the  third  molars  (wisdom  teeth)  not  un- 
til the  child  is  about  three  years  of  age.  The  process 
of  calcification  of  the  twelfth-year  molars  does  not 
commence  until  the  child  is  about  three  years  of  age, 
and  that  of  the  wisdom  teeth  not  until  about  the 
twelfth  year. 


CHAPTER  V. 

ERUPTION  OF  THE  TEMPORARY  TEETH. 

AT  about  the  fifth  month  after  birth  the  process 
known  as  the  eruption  of  the  teeth  begins  —  a 
double  process,  consisting  of  the  gradual  elongation 
and  rising  of  the  teeth,  and  the  coincident  absorp- 
tion of  the  hard  and  soft  tissues  overlying  them.  The 
alveolar  borders  are  the  first  to  show  signs  of  the 
absorptive  process  by  a  dissolution  or  melting  of  their 
approximated  edges,  thus  gradually  making  a  wider 
space  for  the  advancing  teeth.  These,  rising  in  their 
sockets  —  the  roots  meanwhile  lengthening  —  press 
upon  the  overlying  gums,  which,  becoming  thinner 
and  thinner,  finally  allow  the  escape  of  the  imprisoned 
teeth.  It  is  not,  therefore,  as  the  common  expression 
of  *' cutting  the  teeth  "  would  indicate,  a  process  of 
laceration,  tearing,  or  cutting,  but  of  removal  of  im- 
peding tissue  by  absorption,  which  allows  the  passage 
of  the  teeth  through  the  gums.  There  is  no  absolute 
uniformity  either  as  to  the  time  or  the  order  of  erup- 
tion. The  rule  is  that  the  lower  teeth  precede  the 
upper  of  the  same  class  two  or  three  months ;    but 

47 


48 


THE   MOUTH  AND    THE    TEETH. 


not  infrequently  the  upper  precede  the  lower  by  the 
iame  difference  in  time.  Again,  the  rule  is  that 
the  teeth  are  erupted  in  pairs,  with  an  interval 
between    the    different    pairs;    but    occasionally   a 

single  tooth  will 

3  _  ^/r^^^^^^i.  ^  appear    a    con- 

*  ^^  siderable     time 

before    its    fel- 
low,     and     in 
other  cases  two 
or    three    pairs 
will  erupt  coin- 
cidently.      Fig. 
XII.    illustrates 
an     upper     de- 
Fig.  XII.  ciduous  or  tem- 
porary    set    of 
teeth,  of  which  five  are  on  each  side.    The  usual  order 
of  their  eruption  is  as  follows  :  — 


2  Central  incisors  (Nos.  i)  between  the    5th  and  8th  months. 

2  Lateral  incisors  (    "     2)        "  "      7th   "    loth        ** 

2  Canines  (    "     3)         "  *'    12th   "    i6th        " 

2  First  molars         (    "     4)         "  "    14th    "    20th        " 

2  Second  molars    (    "     5)        "  "   20th   "    36th        " 


The  lower  set  consists  of  the  same  number  of  teeth, 
known  by  the  same  names.  They  appear,  as  a  rule, 
in  the  same  order  as  the  upper  teeth,  generally  pre- 


ERUPTION  OF   THE    TEMPORARY   TEETH. 


49 


ceding  the  latter  by  a  few  weeks.     Fig.  XIII.  is  a  side 
view  of  a  child's  lower  jaw.     The  teeth  in  Fis;s.  XII. 


Fi-.  xin. 


and  XIII  marked  6  do  not  belong  to  the  temporary 
set.     They  will  be  treated  of  in  a  separate  chapter  — 
"The  Sixth-Year  Molars." 
5  I> 


CHAPTER   VL 

DIFFICULT    DENTITION. 

THE  eruption  of  the  teeth  is  a  natural  process 
which,  under  conditions  in  every  way  favorable, 
may  take  place  with  little  or  no  disturbance  or  dis- 
comfort to  the  child.  When  the  growth  of  the  teeth 
and  absorption  of  the  guras  proceed  in  perfect  accord, 
the  teeth  may  be  erupted  without  attracting  the  atten- 
tion of  even  a  watchful  mother.  But  comparatively 
few  such  instances  occur.  It  is  rare  for  a  child  to 
pass  through  the  period  of  dentition  without  more  or 
less  manifestation  of  suffering,  and  frequently  there 
are  serious  and  alarming  disturbances  of  its  health. 
It  is  a  well-known  fact  that  this  is  the  period  of  great- 
est mortality  among  children.  It  is  true  that  during 
the  same  period  other  and  important  changes  are 
taking  place  in  the  organization  of  the  child,  especially 
in  the  stomach  and  intestinal  tract,  which  are  intended 
to  prepare  them  to  receive  and  digest  solid  food  — 
changes  which  may  be  said  to  be  concordant  with  the 
development  of  the  masticatory  apparatus.  Doubt- 
less, these  concurrent  changes  exercise  their  full  share 

50 


DIFFICULT  DENTITION.  5 1 

in  producing  constitutional  disturbances  at  this  epoch. 
This,  however,  makes  it  only  more  imperative  that 
the  child  shall  have  even  more  than  usual  hygienic 
care  and  freedom  from  all  avoidable  disturbing  in- 
fluences j  for  whatever  tends,  by  modifying  the  gen- 
eral health  unfavorably,  to  lower  the  resisting  power 
of  the  organism,  may  readily  convert  the  natural  and 
otherwise  easy  course  of  dentition  into  one  of  pain 
and  danger. 

There  is  certainly  during  the  period  of  dentition 
an  increased  susceptibility  to  nervous  and  digestive 
troubles,  requiring  more  than  ordinary  watchfulness 
of  the  child  on  the  part  of  the  mother.  Causes  which 
at  other  times  have  no  appreciable  effect  may  then  be 
fraught  with  danger.  An  exposure  to  cold,  an  attack 
of  indigestion  —  anything  which  introduces  inhar- 
mony  into  the  functions  of  the  animal  life  —  may 
result  in  a  disturbance  of  the  processes  of  dentition. 

Difficult  dentition  may  therefore  be  charged  with 
causing  or  aggravating  various  disorders,  as  these  on 
the  other  hand  may  be  reasonably  suspected  of  inter- 
fering with  the  natural  eruption  of  the  teeth.  It  is 
certainly  unsafe  to  ignore  the  complications  possibly 
due  to  dentition,  if  any  derangement  of  the  health 
of  the  child  occur  during  the  period  when  the  teeth 
are  erupting. 

As  a  rule  the  amount  of  irritation  holds  a  relation 
to  the  number  of  teeth  advancing  simultaneously;  but, 


52  THE   MOUTH  AND    THE    TEETH. 

owing  to  the  varying  susceptibility  of  individuals,  a 
single  tooth  may  cause  more  disturbance  in  one  case 
than  a  half  dozen  will  in  another. 

At  the  commencement  of  the  eruption  of  the  teeth 
there  is  generally  an  increased  flow  of  saliva,  which 
keeps  the  mouth  moist  and  cool.  When  the  irrita- 
tion increases,  and  the  mouth  becomes  hot  and  dry, 
other  derangements  are  likely  to  follow :  the  child 
becomes  feverish  ;  constipation  or  diarrhea  ensues  — 
the  latter,  if  not  too  severe  or  too  protracted,  being 
beneficial,  however,  rather  than  hurtful,  but  requir- 
ing nevertheless  great  care  that  it  does  not  itself  be- 
come a  source  of  danger.  An  unusual  redness  of  one 
or  both  cheeks,  sometimes  changing  from  one  to  the 
other,  is  a  frequent  symptom  of  nervous  disturbance. 
Eruptions  are  apt  to  appear,  usually  on  the  cheeks, 
but  sometimes  on  the  head,  or  even  over  the  whole 
body,  and  ulcerations  on  the  tongue,  gums,  lips,  or 
on  the  inside  of  the  cheeks.  Itching  of  the  nose, 
twitching  of  the  muscles,  dilatation  of  the  pupils, 
uneasiness  and  fretfulness,  restless  sleep  or  wakeful- 
ness, thirst  and  loss  of  appetite,  are  evidences  of  in- 
creasing irritation,  which,  if  not  relieved,  will  be 
followed  by  more  active  manifestations.  The  child 
becomes  cross,  resentful,  moans  when  asleep,  cries 
persistently  when  awake,  or,  if  quiet  for  an  instant, 
will  be  found  chewing  its  thumb  or  fingers,  which 
operation  seems  to  afford  a  momentary  cessation  of 


DIFFICULT  DENTITION.  53 

anguish  —  but  only  momentary.  It  throws  down  its 
toys  as  though  in  a  passion,  refuses  to  be  amused,  and 
treats  all  effort  to  divert  it  as  an  indignity ;  com- 
presses its  lips,  corrugates  its  brow,  shows  an  intoler- 
ance of  light,  pulls  at  its  hair  or  ears,  slaps  or  scratches 
its  nurse,  refuses  its  food,  or  vomits  it  as  soon  as  swal- 
lowed. Further  manifestations  of  increased  consti- 
tutional disturbance  are  likely  to  appear  in  persistent 
and  copious  diarrhea,  nausea,  high  fever,  and  not 
infrequently  convulsions. 

There  is  reason  to  believe  that  earache  is  often  as- 
sociated with  and  dependent  upon  the  difficult  erup- 
tion of  one  or  more  teeth,  and  that,  apart  from  the 
aggravation  of  the  fever  and  the  increased  liability 
to  convulsions  incident  to  this  added  anguish,  there 
is  also  the  possibility  of  the  loss  of  hearing  (entail- 
ing in  young  children  the  loss  of  speech),  from  the 
congestion  and  inflammation  which  result.  But  this 
is  not  the  only,  indeed  not  the  chief,  danger;  the 
inflammation  is  liable  to  extend  to  the  membranes  of 
the  brain  ^nd  end  in  death.  The  facility  with  which 
an  irritation  originating  in  the  mouth  may  be  con- 
tinued to  the  ear,  and  thence  to  the  brain,  can  only 
be  understood  by  a  recognition  of  the  intimate  rela- 
tions w^iich  exist  —  especially  in  the  infant  —  between 
the  parts  concerned,  and  of  their  elaborate  nervous 
connections ;  but  the  danger  is  a  real  one,  and  should 
5* 


54  THE   MOUTH  AND    THE    TEETH. 

never  be  lost  sight  of  in  the  treatment  of  a  child  suffer- 
ing from  teething. 

The  usual  indications  in  the  mouth  of  the  advance- 
ment of  the  teeth  are  increased  heat,  redness,  swelling 
and  hardness  of  the  gum,  and  later  the  peculiar  white- 
ness caused  by  the  pressure  of  the  coming  tooth. 
Sometimes  the  swelling  takes  the  form  of  a  little 
tumor,  like  a  boil,  on  the  edge  of  the  gum ;  in  other 
cases  an  ulceration  will  form  over  the  presenting  tooth. 
In  all  such  conditions  the  gums  are  very  tender,  so 
sensitive  that  the  lightest  touch  will  cause  pain,  and 
the  child,  on  attempting  to  take  the  breast,  will  jerk 
back  its  head  —  a  maneuver  which  is  frequently  mis- 
taken as  an  evidence  of  colic.  A  little  watchfulness 
on  the  part  of  the  nurse  will  enable  her  to  distinguish 
the  difference  between  the  indications  of  the  two 
troubles. 

Sometimes,  however,  the  irritation  of  dentition 
may  produce  the  most  serious  constitutional  derange- 
ments without  any  local  manifestations.  That  such 
may  be  the  case  is  apparent  when  the  conditions  of 
the  parts  concerned  are  understood.  The  troubles  of 
dentition  are  caused  to  some  extent,  doubtless,  by  the 
direct  pressure  of  the  advancing  teeth,  and  the  conse- 
quent irritation  of  the  nerves  of  the  gums ;  but  this 
is  not  the  only,  nor,  it  is  believed,  the  principal  fac- 
tor in  the  disturbance.  It  must  be  borne  in  mind  that 
at  the  time  of  eruption  the  roots  of  the  teeth  are  not 


DIFFICULT  DENTITION.  55 

yet  complete ;  that,  instead  of  the  conical  termi- 
nation and  minute  opening  which  characterize  the 
root  of  the  perfected  tooth,  the  aperture  is  quite 
large,  and  its  edges  thin  and  sharp.  In  estimating, 
therefore,  the  mischief  which  may  result  because 
of  a  lack  of  accordance  between  the  eruption  of 
a  tooth  and  the  absorption  of  the  tissues  which 
impede  it,  we  may  imagine  the  sensitive  nerve  — 
which,  when  exposed  by  decay,  is  so  intolerant  of 
contact  even  with  the  atmospheric  air  —  held  be- 
tween the  bony  socket  and  the  sharp  edge  of  the  in- 
complete root  by  the  backward  pressure  of  the  re- 
sisting gums,  thus  giving  rise  to  a  true  toothache, 
comparable  only  to  that  exquisite  torture  which  is 
experienced  in  after-life  from  an  exposed  and  irri- 
tated pulp.  It  is  not  difficult  to  comprehend  that 
a  free  division  of  the  gum  over  the  tooth  or  teeth  thus 
situated  may,  by  removal  of  the  pressure,  give  imme- 
diate and  complete  relief.  This  simple  operation  of 
dividing  the  gum  over  the  teeth  which  are  next  in 
the  order  of  eruption  is  surely  justified  by  local  mani- 
festations such  as  have  been  specified ;  it  is  also  sug- 
gested by  the  occurrence  of  the  usual  symptoms  of 
difficult  dentition,  even  when  there  does  not  exist  a 
single  local  indication  in  the  mouth.  Under  such 
circumstances  it  would  seem  proper  to  give  the  child 
the  benefit  of  the  doubt  by  free  incisions  over  the  teeth 
whose  eruption  is,  in  accordance  with  general  expe- 


56'  THE  MOUTH  AND    THE    TEETH 

rience,  to  be  anticipated — especially  as  the  operation 
causes  only  a  trifling  amount  of  pain,  inflicts  no  in- 
jury, and  is  practically  free  from  danger. 

The  objections  which  are  generally  made  against 
lancing  may  be  summed  up  as  follows :  That  it  is  un- 
necessary because  of  the  comparative  insensibility  of 
the  gum  tissue,  and  because  the  progression  by  growth 
of  a  tooth  is  inadequate  to  make  pressure  sufficient  to 
cause  serious  discomfort ;  that  it  inflicts  pain  upon 
the  child ;  that  it  is  liable  to  injure  the  developing 
tooth ;  that  there  is  danger  of  serious  hemorrhage 
following  ;  that  there  is  an  increased  resistance  to  the 
eruption  of  the  tooth  by  the  cicatrix  or  scar  which 
results,  and  that  a  repetition  of  the  operation  is  often 
necessary. 

The  first  objection  named  finds  answer  in  the  im- 
mediate, manifest,  and  complete  relief  to  the  infant 
which  so  often  follows  the  operation  that  the  rela- 
tion of  cause  and  effect  is  apparent  to  every  observer ; 
finds  answer,  also,  in  the  testimony  of  every  adult 
who  has  experienced  the  comfort  resulting  from  the 
employment  of  the  lancet  in  the  case  of  difficult  erup- 
tion of  a  wisdom  tooth.  That  the  amount  of  pain 
inflicted  is  of  the  most  trifling  character,  may  be  in- 
ferred from  the  readiness  with  which  a  child,  old 
enough  to  appreciate  conditions,  submits  to  the  oper- 
ation after  it  has  once  realized  its  benefits.  Only  an 
ignorance    of  the    anatomy   of  the    mouth   entirely 


DIFFICULT  DENTITION.  5/ 

inexcusable  in  any  dentist  or  physician  could  lead  to 
the  infliction  of  permanent  injury.  The  liability  to 
serious  bleeding  from  such  use  of  the  lancet  is  so 
small  that  it  is  not  worth  considering  as  a  danger  in 
comparison  with  the  vastly  greater  risk  incurred  by  its 
non-employment  when  indicated.  The  assumed  in- 
creased resistance  of  the  cicatricial  or  scar  tissue  is  as 
unfounded  as  it  is  common.  Even  though  the  wound 
made  by  the  lancet  should  heal  completely  before  the 
eruption  of  the  tooth,  the  scar  tissue  is  less  instead  of 
more  resistant  than  the  original  structure,  and  is  easier 
of  absorption.  This  fact  is  illustrated  by  the  readi- 
ness with  which  a  ''cracked  lip"  in  winter  cracks 
again  in  the  same  place,  although  seeming  to  have 
been  perfectly  healed.  That  a  more  or  less  frequent 
repetition  of  lancing  for  the  relief  of  the  same  tooth 
is  sometimes  necessary,  is  because  of  a  persistence  of 
the  conditions  which  required  the  first  incision. 

The  reasons  for  the  methods  of  lancing  which  are 
considered  to  promise  the  best  results  are  easy  of  com- 
prehension. Premising  that  the  object  of  lancing  is 
not  merely  nor  chiefly  to  induce  a  flow  of  blood,  but 
to  remove  tension,  it  follows  that  the  cuts  should  ex- 
tend through  the  gum  to  the  presenting  surface,  and 
should  be  made  with  special  reference  to  the  form  of 
the  coming  tooth.  The  incisors  need  only  a  divi- 
sion of  the  gum  in  the  line  of  the  arch.     The  molars 


S8 


THE   MOUTH  AND    THE    TEETH. 


require  a  crucial  incision,  as  shown  in  Fig.  XIV.  In 
the  case  of  either  of  the  incisors,  supe- 
rior or  inferior,  owing  to  their  straight 
edges,  the  slightest  appearance  of 
the  tooth  through  the  gum  gives  en- 
Fig.  XIV.  ^|j.g  relief  so  far  as  that  particular 
tooth  is  concerned.  Not  so,  however,  with  the  cus- 
pids and  molars.  The  cuspids,  it  will  be  remem- 
bered, have  cone-shaped  crowns,  and  therefore,  even 
after  the  eruption  of  the  points,  still  keep  up  the 
pressure  by  reason  of  the  inclosing  ring  of  gum,  as 
shown  in  Fig.  XV.  A  complete  severance  of  this 
ring  on  the  lateral  sur- 
faces, as  well  as  on  the  an- 
terior and  posterior  faces, 
as  shown  in  Fig.  XVI.,  is 
necessary  to  relieve  the 
tension.  So,  all  the  cusps 
or  points  of  a  molar  tootli 
may  have  erupted,  and  yet  bands  of  gum  tissue  around 
and  between  them,  as  shown  in  Fig.  XVII. ,  maintain  a 
resistance  as  decided 
as  before  their  ap- 
pearance, but  which 
is  entirely  overcome 
by  cuts  as  shown  in 
Fig.  XVIII.  If,  after  lancing,  the  cuts  should  heal  be- 
fore the  tooth  is  fairly  through  the  gum,  the  operation 


Fig.  XV. 


Fig.  XVI. 


Fig.  XVII. 


Fig.  XVIII. 


DIFFICULT  DENTITION.  59 

should  be  repeated  as  often  as  is  necessary.  Some- 
times, but  not  often,  there  is  a  little  too  much  bleed- 
ing, generally  caused  by  the  child  sucking  the  gums, 
incited  thereto  by  the  taste  of  the  blood.  In  such 
case  the  substitution  of  the  breast  of  the  nurse  will 
give  the  infant  better  employment.  The  extent  of 
the  bleeding  can  be  ascertained  by  touching  the 
wound  occasionally  with  a  napkin-covered  finger,  and 
when  it  continues  longer  than  seems  desirable,  a  little 
very  finely-powdered  alum,  rubbed  into  the  incisions, 
almost  certainly  controls  it.  If  this  fails,  and  the 
case  should  require  the  attention  of  the  physician  or 
dentist,  the  trouble  is  still  quite  amenable  to  treat- 
ment. 


CHAPTER  VII. 

CARE  OF  THE  TEMPORARY  TEETH. 

THERE  is  a  marked  structural  difference,  consist- 
ent with  the  length  of  service  required,  between 
the  temporary  and  the  permanent  teeth  —  a  modifica- 
tion in  the  proportions  of  their  constituents.  The 
temporary  teeth  contain  a  much  larger  amount  of 
animal  matter  than  the  permanent ;  are  consequently 
of  a  less  dense  texture,  and  therefore  more  liable  to 
rapid  decay.  The  pulps  of  the  deciduous  teeth  are 
relatively  larger  than  those  of  the  permanent  set,  and 
when  nearly  or  quite  exposed  by  decay  are  more  sus- 
ceptible to  the  action  of  irritating  agents,  and  are 
more  likely  to  lose  their  vitality  under  untoward  in- 
fluences. For  these  reasons  they  need  even  more 
care  and  attention  than  the  permanent  teeth.  The 
temporary  teeth  are  intended  to  perform  important 
offices,  and  their  retention  in  the  mouth  in  a  healthy 
condition  until  their  successors  are  ready  to  appear 
is  very  desirable.  Besides  their  value  in  the  mastica- 
tion of  food,  they  probably  assist  in  the  development 
of  the  jaws ;  certainly  their  too  early  loss  may  result 

60 


CARE    OF   THE    TEMPORARY  TEETH.  6 1 

in  an  irregular  condition  of  the  second  or  permanent 
set,  producing  a  disfiguration  of  the  mouth  and  in- 
terfering with  the  comeliness  of  the  face  throughout 
life.  The  premature  extraction  of  the  temporary- 
molars  is  fraught  with  danger  to  the  bicuspids. 
These  latter,  as  will  be  seen  by  reference  to  Fig. 
XIX.  (see  p.  69),  are  located,  during  development, 
in  the  crotches  of  the  roots  of  the  former,  the  ex- 
traction of  which  may  inflict  permanent  injury  upon 
them. 

It  is  a  mistake  to  suppose  that  the  temporary  teeth 
may  be  extracted  at  any  time  without  injury.  The 
domestic  dentistry  which  watches  for  the  first  evidence 
of  their  loosening  in  order  that  they  may  be  promptly 
removed,  is  generally  a  mischievous  interference. 
Another  mistaken  notion  is  that  the  temporary  teeth 
were  intended  to  be  lost  by  decay,  and  in  this  manner 
to  make  room  for  their  successors.  Under  favorable 
conditions  they  ought  not  to  decay  at  all,  but  after 
they  have  fulfilled  their  mission  they  should  drop 
out  as  white  and  clean  as  when  they  first  appeared. 
If  allowed  to  decay,  their  pulps  become  exposed, 
giving  rise  to  pain,  leading  generally  to  extraction 
of  the  teeth  ;  or,  if  the  pulps  die  because  of  the  expo- 
sure, gum-boils  form  and  interfere  with  mastication. 
Moreover,  when  the  pulp  of  a  temporary  tooth  dies, 
absorption  of  the  roots  is  arrested,  and  the  tooth  re- 
mains to  cause  soreness,  inflammation,  and  suppura- 
6 


62  THE  MOUTH  AND    THE    TEETH. 

tion  —  sometimes  to  be  a  mechanical  obstacle  to  the 
advance  of  the  succeeding  tooth,  which,  as  a  result, 
may  assume  a  position  inside  or  outside  instead  of  in 
the  line  of  the  arch.  Though  the  premature  loss  of 
the  temporary  teeth  is,  as  a  rule,  to  be  deplored,  there 
are  cases  in  which  the  extraction  of  one  or  more  of 
them  at  the  opportune  time  will  save  much  trouble  in 
securing  a  regular  alignment  of  the  permanent  set. 

The  exemption  of  children  from  the  suffering  caused 
by  dental  decay,  and  the  immunity  of  the  parent  from 
the  consequent  inconvenience,  will  be  best  secured  by 
constant  attention  to  the  teeth  from  their  first  appear- 
ance. The  general  health  of  the  child  will  also  be 
promoted  by  keeping  them  in  such  a  condition  that 
mastication  can  be  performed  without  pain ;  other- 
wise the  child  will  soon  learn  to  avoid  that  which  is 
troublesome  or  painful,  and,  by  swallowing  its  food 
without  proper  mastication,  will  bring  upon  itself  all 
the  evils  of  indigestion.  In  infancy  the  mother  should 
make  it  a  part  of  her  daily  care  of  the  child  to  secure 
perfect  cleanliness  of  its  teeth.  Becoming  thus  accus- 
tomed to  it,  the  child  when  old  enough  to  rinse  the 
mouth  properly  or  to  use  the  brush  will  find  it  impos- 
sible to  feel  comfortable  after  a  meal  until  the  teeth 
have  been  cleansed ;  the  habit  thus  early  formed  is 
almost  sure  to  be  continued  through  life.  Small,  soft 
tooth-brushes  and  pleasant  dentifrices  are  now  manu- 
factured exactly  suited  for  children's  use.     In  cases 


CARE    OF  THE    TEMPORARY  TEETH.  63 

where,  in  spite  of  all  the  care  given  them,  the  tem- 
porary teeth  show  symptoms  of  decay,  equal  or  even 
greater  care  than  would  be  given,  to  the  permanent 
teeth  under  similar  conditions  should  be  taken  to 
prevent  its  extension,  and  cavities  of  decay,  particu- 
larly in  the  molars,  should  be  filled  with  some  one  of 
the  various  preparations  now  in  the  hands  of  the 
dental  profession.  A  good  rule  is  to  have  a  dentist 
examine  the  mouth  of  the  child,  after  it  is  two  and 
a  half  years  old,  at  least  twice  a  year,  or  oftener  if 
necessary. 


CHAPTER    VIII. 

SIXTH-YEAR    MOLARS. 

IT  must  not  be  forgotten  that  the  eruption  of  the 
second  set  begins  before  any  of  the  first  teeth  are 
shed.  Thus,  between  five  and  a  half  and  six  and  a 
half  years  of  age  the  first  permanent  molars,  four  in 
number  —  one  on  each  side  of  the  upper  and  lower 
jaws  —  make  their  appearance.  These  are  commonly 
supposed  by  parents  to  belong  to  the  first  set,  and 
therefore,  if  found  decayed  shortly  after  their  erup- 
tion, no  attention  is  paid  to  them,  because  it  is 
thought  that  they  will  soon  have  to  make  room  for 
their  successors,  and  before  the  error  is  discovered  the 
mischief  is  irreparable.  Although,  as  already  stated, 
the  crowns  of  the  teeth  are  fully  formed  before  their 
eruption  through  the  gum,  the  structures  of  the  tooth 
have  not  then  attained  the  compactness  and  hardness 
which  subsequently  characterize  them,  and  do  not 
acquire  their  maximum  density  for  months,  or  even 
years.  Consequently  decay  makes  greater  ravages  in 
a  given  time  in  youth  than  at  any  subsequent  period, 
except  probably  during  sickness.    There  is,  for  reasons 

64 


SIXTH-YEAR   MOLARS.  65 

not  perhaps  fully  understood,  a  great  liability  in  the 
sixth-year  molars  to  deep  fissures  with  imperfect  union 
of  the  enamel  edges,  and  from  this  and  other  causes  a 
special  tendency  to   caries,  so   that    these  teeth   are 
quite  frequently  decayed  before  they  are  fully  erupted. 
This  fact  shows  the  importance  of  extra  care  and  more 
prompt  attention  to  them ;   for,  if  they  can  be  pre- 
served until  they  become  thoroughly  solidified,  their 
liability  to   decay  is   very  much   lessened,  and    the 
chances  of  retaining  them  throughout  life  are  cor- 
respondingly increased.     The  sixth-year  molars  are 
the  largest  teeth  in  the  mouth.     In  Figs.  XII.  and 
XIII.  (pp.  48,  49)  they  are  shown  in  their  relation 
to  the  temporary  set  —  in  a  child  of  about  six  years 
of  age.     In  Figs.  XX.  and  XXI.  (pp.  71,  72),  these 
same  teeth  are  illustrated  in  their  relation  to  the  per- 
manent set.     They  are  very  important  teeth  in  many 
respects,  and  should  never  be  allowed  to  suffer  from 
decay  if  by  any  possibility  it  can  be  avoided.     Even 
if  they  cannot  be  permanently  saved,  there  are  good 
reasons,  with  reference  to  the  preservation  of  the  integ- 
rity of  the  arch,  why  they  should  be  retained  up  to  a 
certain  period,  viz.,  to  that  between  the  tenth   and 
twelfth  years  —  the  time  when  the  twelfth-year  molars 
are  aboiit  to  appear  ;  there  are  equally  good  reasons 
why,  if  they  cannot  be  retained  with  a  fair  prospect  of 
their  permanent  preservation,  they  should  be  extracted 
at  that  particular  time.      Another  fact  which  should 
6  -"■  T^ 


66  THE   MOUTH  AND    THE    TEETH 

make  each  one  of  these  teeth  the  object  of  special 
anxiety  on  the  part  of  the  parent  is  that,  in  the  opin- 
ion of  many  practitioners  of  ripe  experience,  the  loss 
of  one  frequently  necessitates  the  removal  of  all  four, 
in  order  to  preserve  the  harmonies  of  articulation. 
It  has  been  stated  in  a  previous  chapter  that  the  teeth 
give  each  other  mutual  support,  after  the  manner  of 
staves  in  a  barrel,  and  that  the  teeth  of  the  two  jaws 
are  so  adapted  to  each  other  that  the  elevations  and 
depressions  upon  their  surfaces  articulate  so  as  to  pro- 
duce the  most  effective  results  in  mastication.  After 
the  extraction  of  a  tooth  the  adjoining  teeth  generally 
change  their  positions  more  or  less,  and  the  natural 
occlusion  is  thereby  interfered  with,  and  to  a  greater 
or  less  extent  impaired.  But,  unless  the  tooth  is  re- 
moved at  the  proper  time,  this  is  the  least  of  the  evils 
likely  to  ensue.  If  too  early,  the  adjacent  teeth  close 
up,  causing  irregularity  when  the  other  teeth  erupt ; 
if  a  little  too  late,  the  space  is  never  perfectly  closed, 
and  the  teeth  on  either  side,  lacking  their  natural  sup- 
port, lean  towards  the  vacant  space  —  tipping  over,  so 
that  the  occlusion  in  mastication  is  constantly  forcing 
them  further  out  of  position.  As  a  result  the  gums 
recede  on  the  sides  next  to  the  vacancy,  the  alveolar 
processes  are  absorbed,  the  unsupported  teeth  be- 
come tender,  painful,  and  loose,  and  are  consequently 
lost ;  those  next  adjoining  are  similarly  affected  and 
lost  in  turn ;  and  so,  as  a  consequence  of  the  extrac- 


SIXTH -YEAR  MOLARS.  6/ 

tion  of  a  sixth-year  molar  after  the  eruption  of  the 
bicuspids  and  the  twelfth-year  molar,  the  side  of  the 
mouth  from  which  it  was  taken  is  ruined  before  mid- 
dle life  is  reached ;  and,  if  the  same  condition  exists 
on  the  other  side,  the  function  of  mastication  is  prac- 
tically destroyed.  Are  not  these  sufficient  reasons  why 
parents  should  feel  the  necessity  for  constant  super- 
vision of  the  sixth-year  molars? 

It  is  a  good  rule  for  parents  to  count  their  children's 
teeth  occasionally  after  the  fifth  year,  and,  when  more 
than  five  are  found  on  either  side  of  either  jaw,  they 
may  know  that  the  sixth  or  last  one  belongs  to  the 
second  or  permanent  set,  and  if  lost  will  never  be  re- 
placed ;  that  if  extracted  except  at  the  exact  time 
when  the  conditions  are  most  favorable,  the  results  may 
be  disastrous  to  the  entire  denture,  more  or  less  inter- 
fering with  comfort  and  health,  and,  by  the  consequent 
prevention  of  perfect  mastication,  leading  to  dyspeptic 
and  intestinal  derangements  tending  to  shorten  life. 
The  want  of  a  proper  appreciation  and  proper  treat- 
ment of  these  sixth-year  molars  is,  it  is  safe  to  say, 
one  of  the  most  fruitful  causes  of  the  defective  masti- 
catory apparatus  of  a  vast  majority  of  people  at  and 
beyond  forty  years  of  age. 


CHAPTER  IX. 

SHEDDING  OF  THE  TEMPORARY  AND  ERUPTION  OF 
THE  PERMANENT  TEETH. 

WHEN  the  small  size  and  delicate  structure  of  the 
jaws  of  an  infant,  and  the  fact  that  the  teeth 
correspond  to  them  in  size,  are  considered,  it  will  be 
apparent  that  the  provision  of  a  second  set,  large  and 
strong  in  proportion  to  the  increased  size  and  strength 
of  the  adult  jaw,  is  a  necessity.  Almost  coincidently, 
therefore,  with  the  development  of  the  germ  of  each 
temporary  tooth,  and  in  what  may  be  termed  an  ap- 
pendage to  the  sac  in  which  it  is  inclosed,  appears 
the  germ  of  its  successor.  The  germ  of  the  first  per- 
manent (sixth-year)  molar  is  formed  independently, 
like  those  of  the  temporary  teeth,  but  gives  off  an 
appendage  in  which  is  formed  the  second  or  twelfth- 
year  molar,  which  in  turn  supplies  an  appendage  for 
the  production  of  the  third  molar  or  wisdom  tooth. 
While,  therefore,  the  development  of  the  temporary 
teeth  is  advancing,  the  germs  of  the  second  or  perma- 
nent set  are  also  progressing.  When  the  former  erupt, 
the  latter  are  in  various,  stages  of  development. 

68 


SHEDDING    OF   THE    TEMPORARY,  ETC.        69 

Fig,  XIX.  illustrates  the  jaws  of  a  child  about  six 
years  of  age,  in  which  the  relations  of  the  two  sets  of 
teeth  are  shown  —  the  temporary  teeth  still  in  position, 
and  the  sixth-year  molars  just  erupting.  The  perma- 
nent incisors,  both  upper  and  lower  —  which  after  the 


Fig.  XIX. 

sixth-year  molars  are  the  next  to  erupt  —  are  the  most 
advanced,  both  as  to  completeness  of  form  and  as  to 
position.  The  canines,  which  are  not  due  until  the 
child  is  between  eleven  and  thirteen  years  of  age,  are 
not  nearly  so  complete  in  form,  nor  so  far  advanced 
towards  eruption. 


JO  THE   MOUTH  AND    THE    TEETH. 

As  the  permanent  teeth  approach  their  full  develop- 
ment, a  process  called  *' absorption  "  is  set  up,  by 
which  the  roots  of  the  temporary  set  are  gradually 
removed.  Little  by  little  the  roots  are  dissolved, 
and  the  particles  composing  them  are  carried  away, 
until  only  the  crowns  remain.  This  absorptive  pro- 
cess does  not  begin  upon  the  roots  of  all  the  tempo- 
rary teeth  at  once,  but  in  the  order  corresponding  to 
their  development  and  eruption.  The  lower  central 
incisors  are  the  first  to  become  loose  and  fall  out ; 
then  the  upper  central  incisors ;  then  the  laterals,  and 
so  on  in  the  order  in  which  they  appeared.  Deprived 
of  their  support  in  the  sockets,  and  retaining  only  a 
slight  attachment  to  the  gums,  the  crowns  are  pushed 
out  by  the  movements  of  the  tongue,  cheeks,  or  lips 
during  mastication,  or  are  picked  out  with  the  fingers. 

The  second  or  permanent  teeth  are  thirty-two  in 
number,  including  twelve  not  found  in  the  temporary 
set,  viz.,  eight  bicuspids  and  four  wisdom  teeth  — 
the  sixth-year  molars  constituting  a  part  of  this  set. 
The  following  table  gives  the  average  time  and  order 
of  eruption  of  the  permanent  teeth,  liable,  however, 
both  as  to  time  and  order,  to  very  considerable  varia- 
tion in  exceptional  cases  :  — 

First  molars, 

Central  incisors,     . 

Lateral       "... 

First  bicuspids, 


5  to 

6  years, 

6  " 

8      " 

7  " 

9      " 

9  " 

lO       « 

SHEDDING    OF   THE    TEMPORARY,  ETC. 


71 


Second  bicuspids,  . 

Canines, 
Second  molars, 
Wisdom  teeth, 


10  to  II  years. 

11  "   13      " 

12  "   14      " 
17  "  21      " 


Fig.  XX.  illustrates  an  upper  permanent  or  adult 
set  of  teeth,  in  which  Nos.  i  are  the  central  incisors  \ 

1  1 


Fig.  XX. 


Nos.  2,  the  lateral  incisors ;  Nos.  3,  the  canines ;  Nos. 
4,  the  first  bicuspids;  Nos.  5,  the  second  bicuspids; 
Nos.  6,  the  first  (sixth-year)  molars ;  Nos.  7,  the  sec- 
ond (twelfth-year)  molars ;  and  Nos.  8,  the  third  mo- 
lars, or  wisdom  teeth. 


72 


THE    MOUTH  AND    THE    TEETH. 


Fig.  XXI.  —  Side  View  of  an  Adult  Lower  Jaw. 


SHEDDING    OF   THE    TEMPORARY,  ETC.        73 

Fig.  XXI.  is  a  side  view  of  the  adult  lower  jaw. 
The  lower  teeth  are  known  by  the  same  names  as  the 
corresponding  teeth  of  the  upper  jaw. 

The  cutting  edges  of  the  incisor  teeth  are,  when 
first  erupted,  divided  into  little  cusps  or  points  (prob- 
ably intended  to  facilitate  their  eruption),  giving  them 
a  saw-like  appearance.  These  points,  after  the  teeth 
have  been  put  into  active  service,  are  soon  worn  down, 
leaving  smooth  and  straight  edges. 

The  period  included  between  the  sixth  and  the 
twelfth  or  fourteenth  year  of  the  child's  life  is  an  ex- 
ceptionally important  one  with  reference  to  the  care 
of  the  teeth ;  their  subsequent  condition  for  life  de- 
pending largely  upon  their  treatment  during  this 
period  —  whether  they  shall  be  useful,  comfortable, 
and  ornamental,  or  the  reverse.  Suitable  attention 
given  to  the  condition  of  the  mouth  during  this  pe- 
riod will,  as  a  rule,  in  a  great  measure  prevent  the 
necessity  of  treatment  in  after  life.  This  attention 
on  the  part  of  the  parent  or  guardian  should  consist 
not  only  in  advising  or  directing  th^  habitual,  thor- 
ough cleansing  of  the  teeth  by  the  child,  but  should  in- 
clude a  personal  supervision  of  the  operation,  in  order 
that  senous  omissions  as  to  time  or  manner  may  not 
occur.  In  addition,  a  systematic  examination  of  the 
mouth  by  a  competent  dentist  should  be  made  at 
frequent  intervals.  It  will  not  do  to  wait  until  the 
child  makes  complaint  of  toothache,  or  until  the 
7 


74  I'HE   MOUTH  AND    THE    TEETH. 

ravages  of  decay  make  themselves  visible  to  the  un- 
professional eye.  Long  before  this  mischief —  irre- 
mediable mischief — may  have  been  done. 

There  is  usually  but  little  trouble  attending  the  sec- 
ond dentition ;  but  occasionally  there  are  consider- 
able pain  and  swelling,  and  sometimes  sore  throat, 
difficulty  in  swallowing,  earache,  and  even  severe 
constitutional  disturbance.  Various  distressing  and 
obscure  nervous  affections  have  been  found  to  depend 
upon  the  eruption  of  a  sixth-  or  twelfth-year  molar. 
The  third  molars  or  wisdom  teeth  of  the  upper  jaw 
are  generally  erupted  without  special  trouble,  except 
that  which  is  the  result  of  their  contact,  by  misdirec- 
tion, with  the  cheek,  causing  ulceration.  The  erup- 
tion of  the  wisdom  teeth  of  the  lower  jaw  generally 
causes  considerable  inconvenience  and  suffering,  ow- 
ing to  their  being  crowded  between  the  second  molar 
and  the  ramus  (the  upright  portion)  of  the  jaw.  The 
space  being  insufficient,  the  gum  is  pressed  between 
the  distal  (rear)  surface  of  the  tooth  and  the  ramus ; 
the  irritation  produces  swelling,  and  this  is  aggra- 
vated by  the  bruising  of  the  gum  —  in  mastication 
or  by  the  teeth  of  the  upper  jaw.  Inflammati^iT 
is  thus  set  up,  which  extends  to  the  soft  tissues 
of  the  adjoining  parts,  making  the  act  of  swallow- 
ing difficult  and  painful,  and  mastication  impossible. 
Sometimes  the  inflammation  results  in  suppuration, 
the  pus  finding  exit  at  points  more  or  less  remote, 


SHEDDING    OF   THE    TEMPORARY,  ETC.         75 

internal  or  external.  The  trouble  in  such  cases  is 
generally  of  short  duration,  and  ceases  upon  the  com- 
plete eruption  of  the  tooth.  Other  cases  require 
lancing  of  the  gum,  or  the  removal  of  the  overlying 
portion  of  gum  ;  sometimes  the  extraction  of  the  tooth 
or  of  the  one  in  front  of  it.  No  general  rule  for  the 
treatment  of  these  cases  can  be  given.  It  will  depend 
upon  the  space  in  the  jaw  and  the  eruption  of  the 
tooth  in  a  natural  or  unnatural  position ;  if  the  latter, 
upon  the  form  of  the  deviation.  The  nervous  suscep- 
tibility and  constitutional  condition  of  the  individual 
must  also  be  taken  into  account.  The  record  of 
troubles  caused  by  the  eruption  of  a  wisdom  tooth 
into  a  crowded  arch  shows  cases  of  ulceration  and 
sloughing  of  the  adjacent  tissues,  disordered  vision, 
earache,  deafness,  headache,  neuralgia,  hysteria,  St. 
Vitus' s  dance,  epilepsy,  lockjaw,  and  various  other  se- 
rious disorders  —  some  exceptionally  severe  cases  end- 
ing in  death. 

At  six,  at  twelve,  and  at  seventeen  years  of  age, 
or  until  the  wisdom  teeth  have  been  fully  erupted,  it 
is  well  for  patients  suffering  from  eye  or  ear  troubles, 
or  from  any  deranged  condition  not  otherwise  ac- 
counted for,  to  seek  the  opinion  of  a  competent  den- 
tist, in  order  to  learn  whether  or  not  an  explanation 
is  to  be  found  in  the  mouth. 


fi    I  ■\.  I- 


CHAPTER   X. 

THE    NUTRITION    OF    THE   TEETH. 

NUTRITION  is  the  process  by  which  the  various 
tissues  of  the  body  are  nourished.  The  source 
of  nutrition  is  the  blood,  essential  to  the  life  of  every 
portion  of  the  body,  in  order  that  it  may  obtain  the 
materials  required  for  development,  and  subsequently 
for  maintenance.  The  teeth  are  no  exception  to  this 
rule,  depending  for  their  vitality  upon  the  blood. 
One  of  the  large  vessels  which  supplies  the  external 
parts  of  the  head  gives  off  branches  which  are  called 
the  dental  arteries.  From  these  smaller  branches  are 
given  off,  which  pass  through  openings  at  the  bottom 
of  the  sockets,  and  then  through  the  hair-like  aper- 
ture (the  foramen)  at  the  extremity  of  each  root ; 
through  the  canals  of  the  roots,  and  into  the  cavity 
in  the  centre  of  each  tooth. 

But  all  use  implies  wear  or  waste,  and  wherever  an 
artery  carries  new  material  for  the  building  or  repair 
of  any  tissue,  it  is  accompanied  by  a  vein  to  bear  away 
the  waste  products,  and  thus  from  birth  to  death  every 
portion  of  the  body  is  continually  undergoing  change 
—  waste  and  renewal.     The  pulp  of  a  tooth  is  com- 

76 


THE   NUTRITION    OF   THE    TEETH.  // 

posed  of  nerves  and  blood-vessels ;  from  the  nerves 
pass  out  on  every  side  minute  fibrils  which  penetrate 
the  dentine ;  from  the  blood  nutriment  is  supplied  to 
every  portion  of  the  tooth,  maintaining  its  vitality. 
In  addition  to  this  provision  for  sustaining  the  life 
of  the  tooth,  the  root  is  covered  by  a  membrane  (the 
pericementum),  from  which  nerves  and  blood-vessels 
pass  into  the  cementum.     Thus,  after  the  dentine  and 
enamel  (which,  as  has  been  previously  stated,  are  de- 
pendent upon  the  pulp  for  their  nutrition)  die  in  con- 
sequence of  the  death  of  the  pulp,  the  tooth  still  re- 
tains a  semi- vitality  by  means  of  its  root-membrane, 
and  may  remain  in  the   mouth  without  discomfort, 
sometimes  for  many  years.     Although  the  death  of 
the  pulp  involves  the  loss  of  vitality  to  so  large  a  por- 
tion of  the  tooth,  and  should  therefore  be  guarded 
against  with  all  possible  care ;  yet  it  should  be  known 
that  even  then,  even  after  the  crown  is  lost  through  de- 
cay, the  root  is  still  valuable,  and  may  serve  as  a  base 
for  an  artificial  crown,  or  may  at  least  assist  in  main- 
taining the  adjoining  teeth  in  position  and  prevent- 
ing the  absorption  of  their  alveolar  processes.    Even  a 
tooth  that  has  been  dislodged  by  accident  or  purposely 
extracted  may  be  successfully  replanted  in  its  socket, 
and,  being  held  in  position  by  ligatures  or  other  me- 
chanical device  for  a  few  days,  will  become  firm  by 
virtue  of  the  re-attachment  of  the  pericementum  and 
the  re-cstablishment  of  a  vital  relation  therewith. 


CHAPTER   XL 

FOOD    IN    ITS    RELATIONS   TO    THE   TEETH. 

THE  blood,  which  as  has  been  said  is  the  source  of 
nutrition  to  every  part  of  the  body,  would  speed- 
ily become  impoverished  if  the  materials  which  it  dis- 
tributes to  all  the  various  tissues  were  not  re-supplied 
to  it.  The  elements  required  for  the  development, 
repair,  and  maintenance  of  the  muscular,  nervous, 
and  bony  systems  do  not  originate  in  the  blood,  but 
must  be  furnished  from  without.  These  elements  are 
derived  from  the  food.  There  is  no  permanent  source 
of  strength  but  in  food.  All  food,  however,  is  not 
alike  nutritious,  and  the  different  parts  of  the  body 
require  different  materials  for  their  formation  and 
sustenance.  Each  organ  and  each  tissue  selects  from 
the  blood  that  which  is  akin  to  its  own  structure  —  like 
appropriating  like.  The  bones  and  the  teeth  require 
certain  earthy  matters.  These  abound  in  some  vari- 
eties of  food,  but  are  deficient  or  absent  in  other 
varieties.  If,  therefore,  the  quality  of  the  blood, 
which  distributes  the  elements  of  nutrition,  depends 
primarily  upon  the  food,  it  follows  that  if  food  defec- 

78 


/ 

FOOD   IN  ITS  RELATIOXS    TO    THE    TEETH,     yg 

tive  in  quality  or  deficient  in  quantity  be  supplied  to 
the  mother  during  gestation,  the  child  will  have  an 
imperfect  organization  of  the  teeth.  So,  if  the  food 
of  the  nursing  mother  be  wanting  in  the  materials  of 
which  the  teeth  are  formed,  there  must  result  a  de- 
ficiency in  the  child's  dental  organs,  just  as,  when  the 
food  of  the  child  at  a  later  period  is  lacking  in  the 
bone-producing  elements,  the  later  erupted  teeth  will 
be  defective.  In  a  word,  if  the  food  of  the  mother 
before  the  birth  of  the  child,  or  during  the  period 
when  it  depends  upon  her  for  its  supply,  does  not 
contain  the  elements  to  meet  the  demands,  healthy 
tissues  will  not  be  formed.  It  is  believed  that  in 
those  cases  where  child-bearing  and  nursing  women 
fail  to  supply  themselves  with  food  containing  the 
earthy  elements,  which  are  then  especially  needed, 
there  is  a  drain  upon  their  own  organizations  by 
which  the  child  is,  to  some  extent,  at  least,  provided 
for  at  their  expense.  Their  own  teeth  show  the  ef- 
fects of  the  starvation  by  an  increased  sensitiveness 
and  rapid  decay.  A  popular  apprehension  of  this  fact 
has  crystallized  into  the  proverb,  ''  For  every  child  a 
tooth."  During  pregnancy  and  while  nursing,  more 
than  usual  attention  should  be  given  to  the  teeth, 
whose  increased  tendency  to  decay  should  be  com- 
bated by  unremitting  effort  and  watchfulness,  in  or- 
der that  the  future  comfort  and  health  of  the  mother 


8o  THE   MOUTH  AND    THE    TEETH. 

may  not  be  endangered  or  her  personal  attractions  be 
lessened  by  the  loss  of  teeth. 

But  the  advantages  of  proper  food  —  that  is,  of 
food  containing  the  earthy  materials  of  which  the 
teeth  are  constructed — are  not  confined  to  the  devel- 
opmental period.  While  such  food  is  of  special  value 
in  furnishing  the  necessary  constituents  for  building 
solid  structures  during  the  time  when  the  teeth  are 
developing,  it  is  also  required  to  sustain  them  in  a 
healthy  condition  through  life.  Well-organized  teeth 
are  composed  mainly  of  mineral  substances,  and  there 
is  no  power  in  the  human  organism  to  create  them 
out  of  materials  which  do  not  contain  them.  It  is, 
therefore,  evident  that  if  these  elements  are  lacking 
in  the  materials  furnished  as  food,  the  teeth,  which  in 
large  part  should  be  composed  of  them,  must  suffer 
by  reason  of  the  deficiency;  for  observation  shows 
that  upon  the  greater  or  less  amount  of  their  mineral 
constituents  largely  depends  the  ability  of  the  teeth 
to  resist  destructive  agencies. 

For  infants  there  is  no  other  food  equal  to  that 
supplied  by  the  breast  of  the  healthy  mother,  and 
for  young  children  no  other  food  so  well  suited  to 
the  digestive  organs,  and  so  capable  of  supplying  all 
the  materials  for  the  growth  of  the  various  tissues  of 
the  body,  as  milk.  Up  to  the  age  of  fourteen  or  six- 
teen years  a  liberal  use  of  milk  is  desirable. 

An  abundance  of  the  necessary  mineral  constituents 


FOOD   IN  ITS  RELATIONS    TO    THE    TEETH.     8 1 

is  found  in  certain  grains,  or  rather  in  certain  parts 
of  these  grains.  Whole  wheat  probably  contains 
more  of  the  essential  elements  of  food  than  any 
other  grain.  Next  in  value  is  oats.  But  it  is  chiefly 
the  outer  portions  of  the  grain  which  contain  the 
bone-forming  material,  and  these  are  generally  dis- 
carded in  the  manufacture  of  flour  so  as  to  produce 
a  whiter  article.  That  which  is  discarded  is  full  of 
nutriment  for  the  bones  and  teeth ;  that  which  is 
retained  is  little  more  nutritious  than  starch.  It  is 
apparent,  therefore,  that  the  liability  of  the  teeth  to 
decay  depends  largely,  first,  upon  their  original  or- 
ganiza'tion,  and  that  th^  character  of  the  organization 
depends  upon  the  supply  by  the  mother  or  nurse  of 
the  mineral  constituents  which  ought  to  enter  into 
their  composition ;  second,  upon  the  regular  supply 
—  especially  in  early  life  —  of  food  containing  these 
constituents.  The  use  of  oatmeal,  of  wheaten  grits, 
or  of  bread  made  from  unbolted  flour,  as  a  part  of 
the  daily  diet  from  childhood  up  to  middle  life, 
would  go  very  far  towards  preventing  dental  caries. 
Alimentary  substances,  according  to  their  character, 
furnish  fat,  produce  heat,  or  supply  muscle,  brain, 
nerve,  bone,  and  tooth  material.  It  is  evident  that 
food  which  does  not  contain  the  required  elements 
will  not  sustain  the  body  in  a  healthy  state.  With 
the  single  exception  of  milk,  no  one  article  of  food 
supplies    all    the    various    requisites.       Milk   should 

F 


82  THE   MOUTH  AND    THE    TEETH. 

form  the  exclusive  diet  of  the  child  until  at  least 
nine  months  of  age,  and  the  principal  diet  for  the 
first  three  years  of  life.  Arrow-root,  corn-starch, 
and  other  farinaceous  foods,  are  positively  injurious 
to  a  child  under  three  months  of  age.  The  secre- 
tion of  saliva  before  that  period  is  scant,  and  is, 
moreover,  deficient  in  a  peculiar  fermentative  prop- 
erty which  is  essential  to  produce  the  change  required 
upon  starchy  foods  to  fit  them  for  digestion.  This 
fermentative  power  is  not  fully  developed  in  the 
saliva  until  the  child  is  about  a  year  old.  Starchy 
foods  should  not,  even  at  a  later  period,  be  made  a 
staple,  because,  though  they  «iay  create  fat,  they  do 
not  contain  the  elements  of  which  muscle,  bone,  and 
tooth-structure  are  built.  After  the  child  is  nine 
months  of  age,  if  weaned,  milk  should  still  be  made 
the  staple ;  but  the  diet  may  be  varied  by  the  addi- 
tion of  oatmeal  (boiled  to  a  jelly),  wheaten  grits, 
barley  flour,  rice,  farina,  sago,  bread-crumbs,  the 
yolk  of  ^gg  with  milk,  chicken  or  mutton  broth. 
After  one  year  of  age,  bread  and  butter,  baked  pota- 
toes, and  ripe  fruits  may  be  gradually  added.  While 
on  the  one  hand  confinement  to  any  one  article  of 
food  (unless  it  be  pure,  rich  milk)  should  be  avoided, 
and  a  varied  diet  allowed,  care  should  be  taken,  on 
the  other  hand,  to  exclude  those  substances  which 
contain  but  little  nutriment  or  are  difficult  of  diges- 
tion,  such    as   pastry,    confectionery   (unless  of  the 


FOOD   IN  ITS  RELATIONS    TO    THE    TEETH.     83 

simplest  forms),  cabbage,  turnips,  the  skins  or  rinds 
of  fruit,  etc.  The  course  which  is  calculated  to  best 
subserve  the  general  interests  of  the  child  is  that 
which  is  also  calculated  to  produce  the  best  results 
in  the  dental  structures. 

It  may  be  remarked  that  any  food,  however  well 
adapted  to  the  development,  nourishment,  and  repair 
of  the  various  parts  of  the  animal  organism,  can 
contribute  to  these  results  only  in  proportion  to  its 
transformation  through  vital  processes.  It  is  there- 
fore necessary  not  only  that  a  varied  and  intelli- 
gently selected  diet  be  supplied,  but  that  the  system 
be  kept  in  condition  to  appropriate  the  materials 
furnished  for  its  sustenance.  Nutrition  comprehends 
digestion,  absorption,  respiration,  circulation,  and  as- 
similation, and  is  that  change  in  nutritive  matters 
by  which  they  assume  the  characteristics  of  the  dif- 
ferent living  tissues  of  the  body.  How  much  to  eat, 
and  what  and  when,  in  order  that  *'good  digestion 
wait  on  appetite  and  health  on  both,"  are  therefore 
topics  worthy  of  careful  study. 


CHAPTER  XII. 

NERVOUS  RELATIONS  OF  THE  TEETH. 

THE  cause  of  so-called  reflex  (reflected)  troubles 
and  the  circle  of  sympathies  between  the  mouth 
and  other  portions  of  the  animal  system  can  only  be 
thoroughly  understood  through  a  familiarity  with  the 
origin,  distribution,  and  relation  of  the  nerves.  The 
limits  of  this  volume  permit  only  a  brief  statement 
of  the  facts  that  the  nerves  are  tubular  cords  of  the 
same  general  substance  or  structure  as  the  two  great 
nervous  centres,  the  brain  and  spinal  marrow ;  orig- 
inating in  one  or  other  of  these,  they  extend  to  every 
part  of  the  body,  communicating  frequently  with  one 
another,  and  having  at  such  points  of  contact  knot- 
like enlargements  known  as  ''ganglia,"  in  which  the 
nerves  from  the  brain  and  those  from  the  spinal  cord 
unite,  and  which  have  been  called  "small  brains," 
—  centres  of  nervous  action,  as  they  send  out  the 
influence  of  both  these  nervous  centres  to  the  parts 
which  they  supply  with  nerves.  In  addition  to  the 
nerves  proceeding  from  the  brain  and  spinal  marrow, 
there  is  a  distinct  nervous  system — called  ''the  great 

84 


NERVOUS  RELATIONS   OF   THE    TEETH.        85 

sympathetic" — which,  though  communicating  with 
both  brain  and  spinal  marrow,  does  not  seem  to  be 
immediately  under  the  control  of  either.  Its  special 
function  is  understood  to  be  the  supply  of  nerve-force 
to  what  are  called  the  muscles  of  involuntary  motion 

—  those  not  under  the  domination  of  the  will  —  such 
as  the  muscles  of  the  heart,  stomach,  intestines,  etc. 

Impressions  are  conveyed  from  the  nervous  centres 

—  the  brain  and  spinal  marrow  —  to  the  surface  of 
the  body,  as  well  as  from  the  surface  to  the  nervous 
centres. 

The  different  nerves  have  various  functions.  Thus, 
there  are  nerves  of  special  sense,  as  those  concerned 
in  hearing,  seeing,  smelling,  tasting ;  nerves  of  sen- 
sation ;  nerves  of  motion ;  nerves  combining  sensa- 
tion and  motion ;  nerves  belonging  to  the  voluntary 
muscles,  as  those  of  the  arms  and  legs ;  and  nerves 
distributed  to  the  so-called  involuntary  muscles.  The 
irritation  of  a  nerve  of  sensation  causes  pain;  of  a 
nerve  of  motion,  muscular  contraction  \  of  the  nerve 
of  the  retina,  the  sensation  of  light ;  of  the  auditory 
nerve,  the  sensation  of  sound. 

"Sympathy"  depends  upon  the  connection  that 
exists  between  two  organs  more  or  less  distant  from 
each  other,  so  that  an  affection  of  one  is  transmitted 
to  the  other.  The  sympathy  may  be  that  of  con- 
tiguity (nearness)  or  that  of  continuity.  The  former 
is  illustrated  by  the  earache,  which  is  frequently  asso- 
8 


S6  THE   MOUTH  AND    THE    TEETH 

ciated  with  an  aching  tooth  ;  the  latter  by  the  exten- 
sion of  an  irritation  or  inflammation  throughout  a 
membrane  that  is  continuous  —  as,  for  instance,  in 
the  sore  mouth  sometimes  associated  with  a  disor- 
dered stomach.  By  "reflex"  is  meant  the  peculiar 
phenomenon  of  an  impression  which  originated  at 
one  point  and  was  transmitted  to  the  nervous  centres, 
and  then  referred  to  another  point  more  or  less  dis- 
tant from  the  source  of  the  irritation ;  illustrated  by 
the  angle  described  by  an  elastic  ball  when  thrown 
obliquely  against  a  wall.  The  ball  does  not  return 
as  when  it  is  thrown  at  right  angles  to  the  wall,  but 
flies  off  at  an  angle  corresponding  to  that  at  which 
it  was  impelled.  This  reflex  action  is  constantly  ex- 
emplified in  the  complaint  of  pain  in  a  tooth  in  one 
jaw  when  the  irritation  originates  in  the  other. 

There  are  twelve  pairs  of  nerves  originating  in  the 
brain,  and  thirty-one  in  the  spine.  The  fifth  nerve, 
having  its  origin  in  the  brain,  and  diagramatically  rep- 
resented in  Fig.  XXII.,  is  the  largest  of  the  cranial 
nerves.  Its  functions  are  various.  It  is  the  great 
sensitive  nerve  of  the  head  and  face,  the  nerve  of  the 
special  sense  of  taste,  the  nutrient  nerve  of  the  teeth, 
and  the  motor  nerve  of  the  muscles  of  mastication. 
It  is  called  the  ''trifacial,"  because  it  is  divided  into 
three  main  branches  known  as  the  "ophthalmic," 
the  "superior  maxillary,"  and  the  "  inferior  maxil- 
lary."    These  main  divisions  again  subdivide,  and 


NERVOUS  RELATIONS    OF    THE    TEETH. 


87 


give  off  branches  to  the  eye  and  eyelids,  the  nose,  the 
ears,  the  forehead,  the  scalp,  the  upper  and  lower  lips, 
the  chin,  the  gums,  the  tongue,  and  the  teeth  of  the 
upper  and    lower   jaws ;    filaments  of  the    maxillary 


Fig.  XXII. 


88  THE  MOUTH  AND    THE    TEETH. 

branches  again  join  the  ophthalmic  branch  and  the 
seventh  nerve  —  the  nerve  to  the  muscles  of  the  face. 
The  fifth  pair  of  nerves  is  remarkable  on  account  of 
its  frequent  communication  with  the  sympathetic  ner- 
vous system,  as  well  as  its  numerous  ganglia  and  its 
varied  functions.  It  is  this  nerve  which  is  spe- 
cially affected  during  the  eruption  of  the  teeth, 
whether  of  the  primary  or  permanent  set.  It  is  the 
irritation  of  this  nerve  during  dentition  which  causes 
convulsions  in  children.  It  is  this  nerve  which  is 
the  seat  of  facial  neuralgia.  It  is  the  relation  which 
this  nerve  bears  to  the  head  and  face  which  is  the 
cause  of  the  various  ''sympathetic"  affections  of  the 
eye,  ear,  etc.,  so  commonly  associated  with  dental 
disorders.  Painful  sensations  resulting  from  irri- 
tation of  one  of  the  branches  of  this  nerve  in  the 
mouth  are  reflected  not  only  to  neighboring  but  to 
remote  organs.  Attention  is  naturally  called  to  the 
teeth  in  those  cases  in  which  pain  is  experienced  in  one 
or  more  of  them;  but  frequently  dental  derangements, 
which  have  subsequently  been  proved  to  be  the  ex- 
citing cause  either  of  constitutional  disturbance  or 
of  pain  in  other  organs  or  of  interference  with  their 
functions,  have  failed  to  attract  attention  by  reason 
of  the  absence  of  any  decided  tokens  of  irritation  in 
the  teeth.  In  such  instances  the  announcement  to 
the  patient  that  pain  outside  of  the  mouth  is  in  any 
way  related  to  the  teeth  is  generally  received   with 


NERVOUS  RELATIONS   OF   THE    TEETH.        89 

distrust  of  the  opinion,  if  not  of  the  practitioner  who 
ventures  the  statement.  Many  cases  are  recorded,  il- 
lustrating how  variously  such  reflected  troubles  may 
express  themselves,  and  how  little  reason  there  fre- 
quently may  be  to  suspect  the  origin  of  the  difficulty. 
There  may  be  no  cavity  of  decay,  no  pain,  no  sore- 
ness, no  external  sign  of  trouble,  but,  from  an  enlarge- 
ment of  the  roots, — a  disease  called  exostosis,  —  or 
from  deposits  in  the  pulp  cavity  of  a  tooth,  there  may 
be  a  disturbance,  from  pressure,  which  will  be  reflected 
to  the  eye,  the  ear,  or  other  organs,  or  may  even  cause 
general  derangement  of  the  health. 

General  systemic  disturbances,  resulting  from  dis- 
eased dental  organs,  might  be  considered  as  impossi- 
ble, were  it  not  for  the  instances  with  which  every  den- 
tal practitioner  is  familiar,  in  which  debility,  sleepless- 
ness, nervous  derangements,  mental  depression,  pal- 
pitation, etc.,  after  resisting  constitutional  medica- 
tion, have  yielded  promptly  to  such  treatment  as  w^as 
found  necessary  to  restore  a  healthy  condition  of  the 
mouth.  Indeed,  so  frequently  have  fretful,  nervous, 
irritable,  despondent  conditions  been  found  to  de- 
pend upon  dental  troubles,  that  it  would  appear  to 
be  a  plain  duty,  in  the  event  of  failure  to  discover 
other  causes  for  such  manifestations,  to  have  the 
mouth  and  teeth  carefully  examined  by  a  competent 
practitioner.  So  many  and  so  varied  are  the  disturb- 
ances radiated  or  reflected  to  other  organs,  or  depend- 
8* 


90  THE  MOUTH  AND    THE    TEETH. 

ent  upon  constitutional  irritation  from  dental  affec- 
tions, that  their  enumeration  in  detail  would  be 
tedious;  but  the  inharmonies  thus  set  up  may  range 
from  a  mere  sense  of  discomfort  up  to  and  include 
the  gravest  and  most  formidable  derangements,  in- 
volving even  life  itself. 

But  the  sympathetic  or  reflex  disturbances  of  har- 
mony, caused  by  dental  irritation,  are  not  more  inter- 
esting or  instructive  than  are  the  converse  manifes- 
tations of  pain  or  discomfort  experienced  in  the  teeth 
but  originating  elsewhere.  A  curious  and  familiar 
illustration,  which  will  help  to  an  understanding  of 
these,  is  found  in  the  effect  produced  on  many,  if 
not  most,  people  through  an  irritation  of  the  auditory 
nerves  by  discordant  or  peculiar  sounds,  such  as  those 
produced  by  the  sharpening  of  a  saw,  the  cutting  of 
cork,  etc.,  which  not  only  "set  the  teeth  on  edge," 
but  send  a  thrill  through  the  system  which  is  described 
as  ''  making  the  blood  run  cold."  Similar  effects  are 
produced  on  impressible  organizations  by  the  contact 
of  the  hand  or  fingers  with  certain  substances.  Many 
persons  have  their  teeth  set  on  edge  and  their  blood 
made  to  run  cold  by  touching  velvet.  Even  those 
who  have  lost  all  their  natural  teeth  and  wear  artificial 
substitutes  assert  that  discordant  sounds,  as  well  as 
the  taste,  even  the  smell,  or  sometimes  merely  the 
mention,  of  sour  fruits  or  drinks,  will  cause  their 
teeth  to  feel  "  on  edge ;  "  just  as  those  who  have  lost 


NERVOUS  RELATIONS   OF   THE    TEETH.       9 1 

a  limb  by  amputation  complain  that  they  still  suffer  at 
times  from  itching,  pain,  or  uncomfortable  sensations 
in  the  missing  member.  Many  of  the  instances  of 
painful  affections  of  the  fifth  nerve  are  well-marked 
examples  of  reflected  sensations,  the  primary  irri- 
tation being  in  the  stomach  or  intestinal  canal.  The 
pain  over  the  eyes  so  commonly  associated  with  de- 
rangement of  digestion,  and  which  may  frequently  at 
once  be  relieved  by  correcting  the  acidity  of  the 
stomach,  is  a  familiar  instance.  The  condition 
popularly  known  as  "biliousness,"  among  numerous 
other  manifestations,  not  seldom  reveals  itself  to 
the  observing  sufferer  by  a  peculiar  discomfort  pro- 
duced in  the  teeth,  which,  variously  described,  may 
be  summed  up  under  the  general  phrase,  "exalted 
sensibility. ' '  An  attack  of  dyspepsia  is  by  many  more 
quickly  recognized  through  disagreeable  sensations 
in  the  teeth  than  by  any  special  stomach  disturbance. 
In  sea-sickness  and  in  sick  headache  the  nausea  is 
sometimes  preceded  by  intense  neuralgia  in  the  teeth 
and  jaws,  promptly  disappearing  if  vomiting  be  in- 
duced. In  some  people  hunger  will  excite  markedly 
disagreeable  sensations  in  the  teeth.  A  case  in  point 
is  that  of  a  gentleman  who,  while  convalescing  from 
typhoid  fever,  was  seriously  annoyed  by  painful  sen- 
sations in  two  of  his  molars  whenever  he  became 
hungry.  These  uncomfortable  sensations  would  rouse 
him  from  sleep,  and  could  not  be  allayed  except  by 


92  THE   MOUTH  AND    THE    TEETH. 

the  introduction  of  food  into  the  stomach,  when  in- 
stant relief  followed.  In  another  curious  case  of  ner- 
vous debility  the  approach  of  a  thunder-storm  or  a 
marked  atmospheric  variation  always  produced  a  most 
tantalizing  sensation  of  discomfort  in  the  teeth,  caus- 
ing them  to  feel  as  though  they  were  denuded  of 
enamel.  The  singular  affection  known  as  ''brow 
ague"  or  malarial  neuralgia  —  which,  by  yielding  to 
quinia,  reveals  its  malarial  origin  —  is  frequently 
alternated  or  is  associated  with  periodical  pain  in 
perfectly  sound  teeth.  Neuralgia  (nerve  pain)  fur- 
nishes various  illustrations  of  reflex  or  radiated  pain, 
the  cause  being  in  a  nerve  centre  in  the  brain,  in  the 
trunk  of  a  nerve  or  in  its  extremity,  or,  by  exchange 
of  communication,  in  the  sympathetic  nervous  sys- 
tem. Thus,  a  neuralgia  originating  in  a  diseased 
tooth  may  express  itself  in  the  face,  scalp,  eyes  or 
ears,  or  in  more  remote  parts,  while  by  the  same 
methods  of  radiation  or  reflection,  reversed,  a  neu- 
ralgia having  a  general  or  constitutional  cause,  as 
malaria,  or  a  local  cause  in  the  stomach  or  else- 
where, may  manifest  itself  in  one  or  more  teeth. 
There  is  a  form  of  toothache,  not  inappropriately 
termed  ''hysteric  toothache,"  which  seems  to  de- 
pend upon  emotional  rather  than  physical  excitants, 
and  is  more  amenable  to  mental  impressions  than 
to  local  or  general  medication.  Rheumatism  some- 
times produces  agonizing  pain  in  the  jaws,  and  either 


NERVOUS  RELATIONS    OF   THE    TEETH.       93 

by  direct  influence,  by  the  sympathy  of  contiguity, 
or  by  radiation,  may  so  powerfully  affect  an  indi- 
vidual tooth  that  the  patient  can  hardly  be  persuaded 
that  instant  and  complete  relief  would  not  follow  its 
extraction.  It  is  apparent,  therefore,  that  many  severe, 
remote,  sympathetic,  and  reflex  derangements  may 
be  associated  with  and  dependent  upon  affections  of 
the  teeth.  It  is  a  sad  mistake  for  either  the  dentist, 
the  physician,  or  the  patient  to  consider  the  teeth  as 
mere  mechanical  organs,  requiring  only  mechanical 
treatment,  and  to  therefore  ignore  their  nervous  rela- 
tions to  the  entire  organism. 


CHAPTER    XIII. 

CONSTITUTIONAL     PECULIARITIES,    VARIETIES,     AND 
DEFECTS    OF   THE   TEETH. 

CONSTITUTIONAL  peculiarities,  or  differences 
existing  between  individuals,  which  are  desig- 
nated as  temperaments,  and  which  are  variously 
manifested  in  height,  weight,  build,  complexion, 
color  of  eyes  and  hair,  etc.,  are  nowhere  more  dis- 
tinctly observable  than  in  the  mouth.  The  size, 
form,  color,  and  density  of  the  teeth ;  the  time  and 
order  of  their  eruption  ;  the  character  of  the  enamel 
—  its  perfect  or  imperfect  continuity ;  the  shape  of 
the  roof  of  the  mouth  —  a  broad  and  flat  or  narrow 
and  high  arch;  proportion  or  disproportion  of  the 
jaws  relatively  to  the  head  and  face  or  to  each  other ; 
the  length  and  size  of  the  tongue ;  the  thickness  and 
muscular  power  of  the  lips;  the  character  of  the 
mucous  membrane  of  the  lips,  cheeks,  and  gums  — 
these  and  various  other  distinctive  differences  are 
marked  evidences  of  constitutional  peculiarities. 
The  teeth,  in  their  physical  characteristics,  con- 
sidered individually  or  relatively  to  each  other  and 

94 


CONSTITUTIONAL   PECULIARITIES,  ETC,        95 

to  the  arch  of  the  jasv,  exemplify  hereditary  trans- 
mission, as  well  as  the  impressions  made  upon  them 
during  their  formative  stage.  The  former  is  illus- 
trated by  the  reproduction  in  the  children  of  pecu- 
liarities in  the  teeth  of  their  parents ;  the  latter,  by 
the  constant  proneness  of  the  teeth  to  decay  in  pairs, 
showing  that  the  unfavorable  impression  which  caused 
their  defective  structure  was  made  upon  both  alike. 
Hare-lip  and  cleft-palate  are  examples  of  defects  de- 
pendent upon  some  arrest  of  development  of  the  child 
before  birth,  and  show  also  the  tendency  to  hered- 
itary transmission  of  physical  imperfections.  The 
differences  between  individuals  in  the  physical  char- 
acter of  the  teeth  (differences  in  their  organization, 
ossification,  and  density,  and  consequently  in  their 
healthfulness,  usefulness,  and  durability)  are  gen- 
erally in  harmony  with  other  constitutional  peculi- 
arities. The  size,  shape,  and  structure  of  the  teeth  in- 
dicate also  their  liability  to  decay  or  their  power  of 
resistance  to  unfavorable  conditions.  The  character 
and  progress  of  decay  vary  also  in  the  several  temper- 
aments not  less  than  does  the  original  structure  — 
liability  to  decay  and  its  character  and  progress  be- 
ing, however,  much  modified  by  the  state  of  the 
general  health.  Teeth  poorly  organized  may,  by 
reason  of  favorable  systemic  conditions,  and  intelli- 
gent, persistent  care,  be  made  to  outlast  those  of 
vastly  superior  original  structure,  but  which  succumb 


96  THE  MOUTH  AXD    THE    TEETH. 

to  unfavorable  constitutional  conditions,  or  to  neg- 
lect. 

Teeth  regular  in  their  positions,  of  large  size,  of  a  rich 
yellow  or  yellowish-brown  color,  with  dentine  dense 
as  ivory,  and  enamel  (perfect  in  its  crystallization 
and  in  smoothness  and  hardness  like  glass)  thickly 
and  evenly  deposited,  represent  a  vigorous,  healthy 
constitution.  Those  irregular  in  their  positions,  small, 
stumpy,  and  incongruous  both  individually  and  rel- 
atively; opaque  and  chalky,  with  enamel  only  semi- 
crystallized,  deficient  in  quantity,  and  irregularly  de- 
posited j  the  dentine  soft  or  friable,  represent  con- 
stitutional poverty.  Teeth  of  the  first  class  exhibit 
ability  to  resist  unfavorable  local  and  systemic  in- 
fluences, in  keeping  with  the  vitality  inherent  in  them; 
while  those  of  the  other  class  have  feeble  power  of  re- 
sistance to  unhealthy  conditions,  in  consonance  with 
the  defective  organization  with  which  they  are  asso- 
.ciated.  Modifications  of  every  possible  variety,  in 
physical  outline,  in  elementary  constitution,  and  in 
size,  color,  and  density,  show  the  relative  wealth  or 
poverty  of  the  organization  ;  show  not  infrequently 
the  blending  of  the  characteristics  of  the  parents  — 
in  some  respects  indicating  the  organization  of  one 
parent,  and  in  some  the  peculiarities  of  the  other. 

Even  in  the  same  mouth  some  teeth  are  more  sus- 
ceptible to  decay  than  the  rest,  owing  to  constitutional 
conditions  at  the  time  of  their  formation,  resulting 
in  different  degrees  of  density  in  their  texture,  and 


CONSTITUTIONAL   PECULIARITIES,  ETC.       9/ 

consequently  of  capability  to  resist  the  action  of  de- 
structive agents.  The  deciduous  teeth  show  by  dif- 
ferences of  organization  the  varying  health  of  the 
mother  during  their  development,  as  the  permanent 
teeth  exhibit  disturbances  occurring  during  their  for- 
mative stage.  The  temporary  interruption  of  nu- 
trition by  acute  infantile  diseases,  such  as  measles 
and  scarlet-fever,  is  generally  recorded  distinctly  in 
the  dental  organs. 

In  addition  to  the  imperfections  described  as  re- 
sulting from  systemic  conditions  (either  of  the  parent 
or  child),  during  the  formative  period  of  the  teeth, 
it  is  important  to  note  another  variety  of  defects  not 
infrequently  associated  with  otherwise  perfect  dental 
structures,  viz.,  that  resulting  from  incomplete  union 
of  the  enamel  at  various  points  in  the  depressions 
found  on  the  grinding  surfaces  of  the  molars  and 
bicuspids.  These  flaws  in  the  continuity  of  the 
enamel  favor  the  lodgment  and  retention  of  food  and 
of  the  secretions  of  the  mouth. 
At  such  points  decay  is  almost  sure 
to  occur,  frequently  extending  un- 
suspected underneath  the  enamel 
until  the  integrity  of  the  tooth  is 
seriously  impaired.  Fig.  XXIII. 
represents  a  vertical  section  of  a  Fig*  XXIII. 
molar  magnified,  in  which  a  is  the  fissure  caused  by 
a  failure  of  the  enamel  edges  to  unite. 
9  G 


CHAPTER  XIV. 

IRREGULARITIES    OF    THE   TEETH. 

THE  value  of  the  teeth,  not  only  for  ornamentation 
and  vocalization  but  also  for  utility  in  mastica- 
tion, depends  very  much  upon  their  regular  position 
in  the  arches  of  the  jaws  and  upon  their  perfect  oc- 
clusion. In  a  faultless  denture  the  upper  and  lower 
teeth  come  together  in  such  a  manner  that  the  ele- 
vations and  depressions  upon  the  opposing  surfaces  fit 
into  each  other  so  as  to  produce  the  most  effective  re- 
sults in  mastication.  When  from  any  cause  this  per- 
fect occlusion  is  prevented,  their  usefulness  is  more  or 
less  impaired.  The  deviations  from  regular  position 
and  occlusion  are  various  and  numerous.  The  disad- 
vantages resulting  include  imperfect  mastication  with 
its  consequent  derangements,  faulty  pronunciation,  in- 
terference with  the  thorough  cleansing  of  the  teeth, 
thus  increasing  their  liability  to  decay ;  irritation  of 
the  gums,  tongue,  lips,  or  cheeks,  and  disfiguration 
of  the  countenance.  The  inconvenience  is  more  or 
less  serious,  and  the  deformity  more  or  less  conspicu- 
ous, according  to   the  character  and   extent  of  the 


IRREGULARITIES  OF   THE    TEETH.  99 

deviation.  The  irregularity  may  be  limited  to  a  false 
position  of  one  or  more  teeth,  or  may  involve  the 
entire  denture;  may  be  the  result  of  some  extrinsic 
cause,  or  of  an  incongruity  of  size  between  the  teeth 
and  the  jaws.  A  single  tooth  is  sometimes  twisted 
upon  its  axis,  overlaps  the  adjoining  tooth,  or  erupts 
inside  or  outside  of  the  arch.  The  latter  occurrence 
—  a  frequent  one  with  the  canines  —  is  generally  a 
source  of  great  annoyance,  interfering  seriously  with 
the  symmetry  of  the  face.  Sometimes  the  upper  front 
teeth  shut  edge  to  edge  against  the  lower,  instead  of 
overlapping  them,  causing  a  rapid  wearing  away  of 
the  edges  of  both.  In  other  instances  the  upper  teeth 
shut  so  far  outside  of  the  lower  ones  that  they  rest 
upon  the  lower  lip ;  or  they  protrude  so  that  the  upper 
lip  fails  to  cover  them.  Another  variety  of  irregularity 
is  that  in  which  the  teeth  of  the  lower  jaw  close  in  front 
of  the  upper  teeth  —  an  inversion  of  order  which  in 
the  dog  is  known  by  the  name  of  ''underhung." 
Another  but  rarer  form  of  irregularity  is  that  in  which 
the  molars  alone  come  in  contact  when  the  mouth  is 
closed,  causing  the  front  teeth  to  stand  apart. 

Irregularities  of  the  teeth  proceed  from  a  variety 
of  causes,  among  which  may  be  mentioned  mechan- 
ical injuries,  such  as  blows  upon  the  mouth ;  the  pres- 
ence of  supernumerary  or  extra  teeth  ;  a  steady  press- 
ure, such  as  is  kept  up  during  the  habit  of  sucking  the 
thumb  or  fingers,  tongue  or  lip^  during  childhood  \  a 


lOO  THE  MOUTH  AND    THE    TEETH. 

too  early  extraction  of  some  of  the  temporary  teeth, 
especially  of  the  molars  and  canines  ;  a  wrong  direc- 
tion given  to  one  or  more  teeth  by  a  mechanical 
impediment,  such  as  the  retention  in  the  mouth  of 
temporary  teeth,  or  even  roots  of  temporary  teeth, 
after  the  time  when  they  should  have  been  removed ; 
hereditary  transmission  of  dental  peculiarities ;  the 
incongruous  association  of  large  teeth  with  small 
jaws, —  a  mixing  without  blending  of  differing  pa- 
rental characteristics, —  as,  for  instance,  large  jaws  and 
large  teeth  in  one  parent,  and  small  jaws  and  small 
teeth  in  the  other ;  if  the  small  jaws  of  one  and  the 
large  teeth  of  the  other  be  associated  in  the  offspring, 
the  result  will  be  an  overcrowded  denture. 

Children  with  enlarged  tonsils  are  liable  to  an 
irregular  disposition  of  the  teeth  as  a  result  of  the 
habitually  open  mouth  caused  by  the  difficulty  of 
breathing  through  the  nose. 

Fig.  XXIV.  illustrates  the  type  of  deformity  result- 
ing from  the  habit  of  thumb-sucking.  A  similar  pro- 
trusion of  the  teeth  of  the  lower  jaw  is  produced  by 
the  habit  of  sucking  the  first  and  second  fingers,  the 
weight  of  the  hand  and  arm  gradually  forcing  the 
teeth  out  of  position. 

In  many  instances  children  are  allowed  to  retain 
the  bottle  from  which  they  have  nursed,  or  are  sup- 
plied with  a  sugar-teat,  or  are  permitted  to  suck  the 
thumb  or  fingers,  because  of  the  quieting  effect  which 


IRREGULARITIES   OF   THE    TEETH.  lOI 

this  occupation  seems  to  produce.  The  resulting  de- 
formity of  the  jaws,  and  the  consequent  irregularity 
of  the  teeth  (crowding,  overlapping,  or  protruding), 
produces  disfiguration  and  causes  disabilities  and  dis- 
comforts which  remain  throughout  life. 


Fig.  XXIV. 

It  is  much  easier  to  prevent  these  habits  or  to  break 
them  up  in  their  incipiency  than  after  they  have  been 
fully  formed,  although  in  some  cases  the  sucking  in- 
stincts of  the  child  make  their  prevention  or  early 
correction  no  easy  task  to  the  anxious  parent.  The 
sugar-teat  can  be  denied ;  the  nursing-bottle  may  be 
removed  as  soon  as  used  ;  but  the  fingers  and  thumbs 
are  not  so  easily  disposed  of,  and  probably  the  absolute 
imprisonment  of  the  hands  will  in  many  instances  be 
required.  Watchfulness  by  the  mother  or  attendant 
during  the  child's  waking  hours  will  be  sufficient  to  pre- 
vent the  indulgence ;  but  during  sleep  extra  precau- 
tions are  necessary.  A  plan  which  has  been  success- 
9* 


102  THE  MOUTH  AND    THE    TEETH. 

fully  resorted  to^  and  which  is  commended  for  its 
simplicity  and  efficiency,  is  to  have  the  child's  night- 
dress made  without  sleeves,  like  a  pillow-case,  and 
fastened  by  a  drawing-string  about  the  neck.  Cer- 
tainly no  pains  which  are  necessary  to  save  the  child 
from  the  evil  effects  of  the  pernicious  habit  of  fruit- 
less sucking  should  be  considered  onerous. 

Chief  in  importance  in  the  list  of  causes  of  irreg- 
ularity is  defective  growth  of  the  jaws  during  the 
development  of  the  permanent  teeth.  In  a  perfectly 
healthy  person  the  teeth  and  the  jaws  would  develop 
harmoniously ;  but  it  is  quite  possible  for  one  or  the 
other,  or  both,  to  suffer  in  development,  according  to 
the  character  of  the  disturbing  influence. 

That  the  operation  of  some  of  the  causes  named 
may  be  clearly  understood^  it  must  be  remembered 
that  previous  to  the  eruption  of  the  teeth  their  roots 
are  not  closely  embraced  by  the  bony  sockets,  as  they 
are  after  they  have  erupted.  During  the  develop- 
ment of  a  tooth  the  socket  is  necessarily  large  enough 
to  contain  the  crown,  which  is  comparatively  so  much 
larger  than  the  root  that,  after  the  former  has  emerged 
from  the  socket,  the  tooth  is  surrounded  only  by  soft 
and  yielding  tissues,  and  hence  is  readily  diverted 
from  its  course  by  even  a  very  slight  impediment.  It 
must  also  be  remembered  that  the  size  of  the  crowns 
of  the  permanent  teeth  is  determined  long  before 
their  eruption,  and  is  not  subject  to  subsequent  modi- 


IRREGULARITIES  OF  THE    TEETH.  IO3 

fications;  that  the  development  of  the  teeth  and  that 
of  the  jaws  proceed  independently  of  each  other,  and 
that  the  teeth  erupt  according  to  their  original  for- 
mation, even  though  the  jaws  be  hindered  in  their 
growth.  Bearing  in  mind  these  facts,  it  is  easily 
understood  that  any  subsequent  interruption  or  inter- 
ference with  the  development  of  the  jaws  must  neces- 
sarily result  in  a  crowded  condition  of  the  teeth.  It 
is  to  such  interruption,  it  is  believed,  that  many  of 
the  irregularities  witnessed  in  the  mouths  of  the  pres- 
ent generation  are  directly  traceable.  If  the  brain 
and  nervous  system  be  unduly  stimulated ;  if  more 
attention  be  bestowed  upon  the  child's  manifesta- 
tions of  intelligence  than  upon  the  growth  of  the 
body  and  the  general  vigor  of  the  system,  the  mus- 
cular and  bony  structures  must  suffer.  An  undue  or 
precocious  mental  development  is  attained  at  the  ex- 
pense of  the  rest  of  the  organism.  An  indoor  life,  • 
late  hours,  stimulating  food,  overheated  sleeping  apart- 
ments, surroundings  which  in  any  way  invite  and 
encourage  mental  precocity,  can  result  only  in  a 
disturbance  of  the  proper  balance  or  symmetry  of  de- 
velopment —  the  bony  and  muscular  systems  and  the 
functions  of  animal  life  being  sacrificed  for  the  sake 
of  a  brilliant  but  probably  brief  intellectual  ascend- 
ency. During  the  first  seven  years  of  a  child's  life, 
the  brain  and  nervous  system,  far  from  being  stim- 
ulated, should   be  carefully,   persistently,   earnestly. 


I04  THE   MOUTH  AND    THE    TEETH. 

anxiously  guarded,  and  their  development  repressed 
instead  of  favored.  There  is  no  necessity  to  teach  a 
child  under  seven  years  of  age  anything  but  morals 
and  manners.  Whatever  is  added  to  these  in  the  way 
of  education  tends  to  inharmony  of  development  —  a 
nervous  and  mental  precocity  at  the  expense  of  the 
physical  organism ;  tends  not  only  to  a  crowded 
denture,  to  imperfect  organization  of  the  teeth,  and 
to  their  early  decay,  but  to  a  general  physical  imper- 
fection, and  too  often  in  addition  to  subsequent  men- 
tal incapacity  or  aberration.  Out-door  life,  childish 
pursuits,  plain  and  wholesome  food,  long  periods  of 
repose  —  all  things,  in  fact,  which  favor  the  health 
and  growth  of  the  physical  organism  —  promote  the 
health  ■and  growth  of  the  jaws  and  teeth,  and  at  the 
same  time  favor  a  mental  development  which,  though 
of  slower  growth,  is  likely  to  be  symmetrical,  vigor- 
ous, and  permanent. 

It  is  much  easier  to  avoid  decided  irregularities  of 
the  teeth  by  attention  at  the  proper  time  than  to  cor- 
rect them  at  a  later  period.  The  nutritive  functions 
are  more  vigorous  and  the  processes  of  absorption 
and  reconstruction  more  active  in  early  life  than  sub- 
sequently. If,  therefore,  changes  of  position  of  one 
or  more  teeth  are  necessary  to  the  correction  of 
an  irregularity,  an  easy  adjustment  is  permitted  in 
childhood,  which  a  few  years  later  would  be  tedious, 
difficult,  and  uncertain.     One  of  the  reasons  for  in- 


IRREGULARITIES   OF  THE    TEETH.  I05 

terference  at  an  early  period,  when  a  tendency  to 
irregularity  is  to  be  combated,  is  because  of  the  fact 
that  false  positions  of  the  teeth  are  made  difficult  of 
correction  when  those  of  the  opposite  jaw  in  closing 
prevent  them  from  assuming  their  correct  relation  to 
the  arch  of  the  jaw. 

The  causes  and  forms  of  irregularity  are  so  numer- 
ous and  various  that  no  rules  can  be  laid  down  for 
treatment.  The  natural  expansion  of  the  jaw  up  to 
a  certain  period,  the  extent  of  the  irregularity,  the 
character  and  condition  of  the  teeth,  the  age  of  the 
patient,  and  various  other  considerations,  will  deter- 
mine the  judgment  of  the  dentist.  Under  the  care 
of  a  competent  adviser,  the  prevention  or  correction 
of  most  forms  of  irregularity  is  neither  difficult  nor 
problematical,  if  the  proper  effort  be  made  in  time. 


CHAPTER    XV. 

TARTAR,    OR   SALIVARY   CALCULUS. 

THE  liquid  (saliva)  found  in  the  mouth  is,  as  has 
been  heretofore  explained,  the  product  of  various 
glands.  It  contains  in  solution  animal  and  earthy 
matters  which  are  liable  to  be  precipitated  upon 
coming  in  contact  with  the  atmosphere,  or  by  reason 
of  the  changes  of  temperature  to  which  it  (the  saliva) 
is  subjected  in  the  mouth.  These  precipitates,  com- 
posed as  stated  of  both  animal  (organic)  and  earthy 
(inorganic)  matters,  mixed  with  mucus  and  with  va- 
rious accidental  substances  (alimentary  debris)  found 
in  the  mouth,  are  deposited  upon  the  teeth.  This 
deposit  is  called  ''tartar"  because  of  its  resemblance 
to  the  article  so  named  which  is  precipitated  from 
wines  and  adheres  to  the  sides  of  the  casks  in  the 
form  of  a  hard  crust. 

The  quantity  of  tartar  deposited  varies  in  different 
persons  and  at  different  periods,  as  do  also  its  chemical 
and  physical  characteristics.  It  is  sometimes  com- 
posed almost  entirely  of  earthy  or  inorganic  ingredi- 
ents ;  sometimes  it  is  largely  made  up  of  animal  mat- 

io6 


TARTAR,  OR  SALIVARY  CALCULUS.  10/ 

ters ;  sometimes  it  is  of  almost  flinty  hardness,  and 
in  other  cases  so  soft  that  it  can  be  scraped  off  with 
the  finger-nail.  Its  color  is  not  uniform,  but  may  be 
black,  brown,  green,  yellow,  or  nearly  white. 

The  amount  and  character  of  the  injury  caused  to 
the  teeth,  gums,  and  sockets  by  the  different  forms 
of  tartar  vary  as  greatly  as  the  quantity,  composition, 
density,  and  color  of  the  deposit.  Some  varieties  form 
in  thin,  hard  scales,  which  can  be  chipped  off  with 
an  instrument.  Other  forms  are  characterized  by  a 
rough,  uneven  surface  and  an  exceedingly  tenacious 
adherence  to  the  teeth.  In  other  cases  it  has  a  con- 
sistence more  like  that  of  cheese.  Some  forms  are 
more  correctly  described  as  stains  than  as  deposits. 
Some  kinds  of  tartar  are  inodorous,  while  others  are 
insufferably  fetid  and  offensive.  Some  act  chiefly  as 
mechanical  irritants  to  the  gums  and  to  the  edges  of 
the  alveolar  processes ;  others  possess  an  acrid  char- 
acter, corroding  the  surfaces  of  the  teeth  on  which 
they  are  deposited,  and  causing  rapid  decay. 

Tartar  is  deposited  most  rapidly  upon  such  teeth 
and  such  parts  of  the  teeth  as  are  nearest  the  open- 
ings of  the  salivary  ducts,  and  is  likely  to  remain 
upon  the  surfaces  which  are  least  exposed  to  the 
friction  of  mastication.  The  inner  surfaces  of  the 
lower  incisors  and  the  outer  surfaces  of  the  upper 
molars  are,  for  both  of  the  reasons  stated,  most  likely 
to  suffer.     Gravity  also  favors  its  lodgment  on  the 


I08  THE  MOUTH  AND    THE    TEETH. 

teeth  of  the  lower  jaw.  The  greatest  accumulation 
takes  place  during  the  night,  because,  the  teeth  not 
being  used  in  mastication,  and  the  fluids  of  the  mouth 
not  being  kept  in  motion  by  the  movements  of  the 
tongue,  lips,  and  cheeks,  there  is  nothing  to  interfere 
with  its  attachment. 

In  certain  cases  the  mischief  occasioned  by  the 
presence  of  tartar  seems  out  of  all  proportion  to  the 
amount  of  the  deposit,  which  insinuates  itself  around 
the  necks  of  the  teeth,  beneath  the  free  edge  of  the 
gums,  working  its  way  insidiously  towards  the  roots, 
thus  separating  the  gums  from  the  teeth  and  the  roots 
from  their  enveloping  alveolar  processes ;  producing 
inflammation,  sponginess,  and  suppuration  of  the  mar- 
gins of  the  gums,  and  causing  them  to  bleed  at  the 
slightest  touch ;  making  the  use  of  the  brush  exceed- 
ingly painful ;  interfering  with  mastication ;  making 
the  breath  offensive ;  vitiating  the  fluids  of  the  mouth, 
and  thus  creating  irritation  of  the  throat  and  bron- 
chial tubes,  indigestion,  and  general  derangement  of 
the  health.  The  early  stages  of  this  condition  are 
manageable,  but  the  only  treatment  available  is  the 
thorough  removal  of  the  tartar  by  a  competent  den- 
tist ;  scoring  the  gums  and  the  use  of  astringent  washes 
being  worse  than  useless.  After  the  removal  its 
re-accumulation  must  be  guarded  against  with  the 
utmost  care. 

There  is  a  variety  of  deposit  or   stain  which  is 


TARTAR,   OR   SALIVARY  CALCULUS.  lOQ 

exceedingly  deleterious.  It  is  of  a  greenish -brown 
color,  and  is  frequently  to  be  found  on  the  front 
surfaces  of  the  upper  permanent  incisors  of  children. 
Owing  to  its  position  beneath  the  lip,  it  is  undisturbed 
by  the  act  of  mastication,  by  the  fluids  of  the  mouth, 
or  by  the  movements  of  the  muscles  in  speech.  It  is 
very  tenacious,  and  has  an  offensive  odor,  or  at  least 
accompanies  a  vitiated  mucous  secretion,  which  ren- 
ders the  breath  offensive.  Its  destructive  effects  are 
made  manifest  by  furrows  eaten  through  the  enamel 
across  the  teeth  just  below  the  margin  of  the  gums. 
The  teeth  of  young  people  are  frequently  ruined  by 
this  variety  of  deposit.  The  affection  seems  to  de- 
pend upon  a  diseased  condition  of  the  mucous  glands, 
the  deposit  recurring  quickly  after  removal.  Treat- 
ment should  be  directed  to  a  correctioji  of  the  cause, 
as  the  mere  removal  of  the  deposit  will  not  result  in 
any  permanent  benefit. 

lO 


CHAPTER  XVI. 

DECAY  OF  THE  TEETH,  OR  CARIES. 

DECAY  of  the  teeth  is  an  affection  which  is  almost 
universal.  It  may  be  defined  as  a  disintegration 
of  the  tooth-structure,  affecting  the  enamel,  the  den- 
tine, and  sometimes,  though  rarely,  the  cementum. 
It  always  commences  on  the  exterior  of  a  tooth,  and 
is  dependent  chiefly  upon  external  influences,  though 
it  may  be  modified  by  constitutional  conditions. 

The  causes  of  decay  are  predisposing  and  exciting. 
The  predisposing  causes  are  imperfect  structure,  ir- 
regularity of  position,  and  mechanical  injuries.  Con- 
ditions inherent  in  the  teeth  by  virtue  of  their  original 
structure,  determined  before  birth  or  during  infancy, 
establish  in  many  cases  a  predisposition  to  decay. 
Owing  either  to  imperfect  health  of  the  mother  dur- 
ing the  development  of  the  teeth,  or  to  disturbances 
of  the  health  of  the  child  during  their  formative  stage, 
the  various  processes  of  organization  are  liable  to  be 
so  interrupted  and  deranged  as  to  result  in  defective 
dental  structures.  The  dentine  is  soft  and  friable ; 
the  enamel  semi-crystallized  and  deficient  in  quantity 

no 


DECAY  OF   THE    TEETH,   OR    CARIES.         Ill 

or  quality  —  a  heterogeneous  mixture  of  animal  and 
earthy  materials.  Teeth  thus  imperfect  in  their  tex- 
ture are  necessarily  not  fitted  to  resist  the  action  of 
destructive  agents.  The  same  may  be  said  of  those 
with  deep  fissures  whose  edges  are  imperfectly  joined. 

Irregularity  of  position,  from  whatever  cause, 
renders  the  teeth  liable  to  decay.  When  they  lap 
over  one  another,  or  touch  at  points  other  than  those 
which  are  intended  to  come  in  contact  in  a  natural 
and  orderly  arrangement,  decay  at  such  points  is  apt 
to  occur.  The  difficulty  of  keeping  irregular  teeth 
clean  is  another  fruitful  cause  of  decay,  the  retention 
of  food  being  favored  by  their  positions. 

Mechanical  injuries  —  falls,  blows,  and  improper 
use  of  the  teeth,  destroying  the  continuity  of  the 
enamel  —  also  predispose  to  decay. 

The  exciting  causes  of  decay  are  chiefly  different 
forms  of  chemical  action,  which  may  either  follow  from 
the  use  of  acids  as  food  or  medicine,  or  be  caused  by 
improper  tooth-powders  or  washes ;  or  may  result  from 
a  vitiation  of  the  secretions  of  the  mouth,  either  from 
a  general  systemic  derangement  or  from  a  local  cause, 
such  as  mumps,  sore  throat,  or  the  presence  of  tartar 
about  the  necks  of  the  teeth  causing  an  irritation  of 
the  gums  and  inducing  an  acid  secretion  ;  or  from  the 
fermentation  and  decomposition  of  food  about  and 
between  the  teeth.  This  latter  is  beyond  question  the 
chief  cause  of  caries.     It  is  well  known  that  in  the  fer- 


112  THE   MOUTH  AND    THE    TEETH. 

mentation  or  decomposition  of  animal  or  vegetable 
substances  acids  are  generated.  Every  housekeeper  is 
aware  of  the  liability  of  milk,  catsup,  and  various 
other  household  supplies  to  turn  sour — a  result  caused 
by  the  development  of  a  microscopic  vegetation  called 
the  "yeast  plant,"  the  change  taking  place  more  read- 
ily in  warm  weather  than  in  cold.  Under  favoring 
circumstances  a  like  growth  (facilitated  by  the  heat 
and  moisture)  takes  place  in  the  mouth,  and  acts 
upon  the  mucus  and  saliva  as  a  ferment.  The  little 
masses  of  food  impacted  in  the  crevices  and  between 
the  adjoining  surfaces  of  the  teeth  thus  become  so 
many  heaps  of  decomposing  or  fermenting  material, 
generating  acids  which  attack  and  destroy,  particle 
by  particle,  the  tooth-structure.  The  effect  of  a 
weak  acid  upon  a  substance  which,  like  the  teeth,  is 
largely  composed  of  a  form  of  lime,  may  be  seen  by 
the  submersion  of  an  ^gg  in  vinegar.  In  a  few  days 
the  ^gg  will  be  entirely  deprived  of  its  shell.  This 
exemplifies  the  manner  in  which  the  acid,  generated 
by  fermentation  of  food,  mixed  with  the  secretions 
of  the  mouth,  attacks,  disintegrates,  and  dissolves 
the  lime  of  the  tooth.  Decay  never  begins  on  the 
smooth  surfaces  of  teeth  —  those  which  are  exposed 
to  the  friction  of  mastication  —  but  always  com- 
mences at  points  which,  owing  to  their  structure  or 
to  their  arrangement,  furnish  convenient  receptacles 
for  decay-producing  agents.     The  points  most  favor- 


DECAY  OF   THE    TEETH,    OR    CARTES.         II3 

able  to  such  retention  are  the  deep  fissures  of  the 
bicuspids  and  molars  and  the  approximate  surfaces 
of  the  teeth.  In  these  crevices,  and  at  the  surfaces 
which  the  teeth  present  to  each  other,  and  which 
favor  the  lodgment  and  retention  of  food  and  mucus, 
decay  is  most  likely  to  begin,  and  once  begun  to 
continue.  It  proceeds  slowly,  perhaps,  so  far  as  the 
enamel  is  concerned,  but  when  it  reaches  the  den- 
tine, either  through  a  fissure  in  the  enamel  or  a 
breach  made  through  its  walls,  it  progresses  more 
rapidly  until  the  pulp  is  reached,  and  its  vitality 
and  the  strength  and  substance  of  the  tooth  are 
destroyed.  Decay  proceeds  much  faster  when  once 
a  cavity  has  been  formed  in  a  tooth  because  the  de- 
structive materials  are  there  held  in  constant  contact 
with  the  tooth-structure;  not,  as  is  generally  supposed, 
because  the  dentine  is  so  much  more  susceptible  to 
their  action  than  the  enamel.  Smooth,  well-polished 
dentine,  such  as  is  left  by  careful  operators  after 
making  what  is  called  a  permanent  separation  be- 
tween adjoining  teeth,  resists  decay  in  many  cases 
almost  as  well  as  the  enamel  itself. 

The  character  of  the  disintegration  to  which  the 
teeth  are  liable  differs,  as  does  their  original  forma- 
tion, in  different  individuals,  the  decay  being  dark, 
white,  dry,  moist,  horny,  soft,  chalky,  or  cartilagi- 
nous, according  to  the  quality  of  the  original  struct- 
ure and  the  strength  and  activity  of  the  solvent ; 
10*  II 


114  ^^-^   MOUTH  AND    THE    TEETH. 

also  somewhat  according  to  the  systemic  conditions 
of  the  individual.  The  teeth  are  a  part,  and  an 
exquisitely  organized  part,  of  the  animal  economy. 
They  must,  therefore,  be  more  or  less  influenced  by 
the  state  of  the  general  health.  They  are  liable  to 
considerable  modification  of  their  texture  by  varying 
constitutional  conditions,  becoming  softer  at  times, 
and  therefore  more  likely  to  be  injuriously  affected 
by  decay-producing  agents.  Moreover,  morbid  se- 
cretions of  the  mouth  in  deranged  systemic  condi- 
tions tend  markedly  to  the  production  of  caries. 
Slight  irritation  of  the  mucous  membrane,  such  as  is 
caused  by  the  presence  of  tartar  which  has  insinuated 
itself  between  the  gums  and  the  necks  of  the  teeth, 
will  provoke  a  mucous  secretion  decidedly  acid,  and 
as  decidedly  destructive  to  tooth-structure.  Derange- 
ments of  the  alimentary  canal  are  generally  accompa- 
nied by  acidity  of  the  saliva.  During  pregnancy  the 
saliva  is  generally  acid  in  character,  which  fact,  in 
addition  to  the  softened  condition  of  the  teeth  them- 
selves previously  alluded  to,  accounts  for  the  rapid 
decay  which  is  undoubtedly  apt  to  take  place  at  such 
times.  In  all  acute  inflammatory  diseases,  and  in 
all  chronic  affections  of  the  digestive  tract,  there  is 
increased  viscidity  of  the  mqcous  secretions  of  the 
mouth  with  a  marked  diminution  of  the  saliva,  tend- 
ing to  the  production  of  caries.  In  dyspeptic  trou- 
bles there  is  generally  an  acid  condition  of  the  diges- 


DECAY  OF   THE    TEETH,   OR    CARIES.         II5 

tive  fluids,  which  are  regurgitated  from  the  stomach 
to  the  mouth  and  act  directly  upon  the  lime  of  the 
teeth. 

In  addition  to  the  acids,  resulting  from  derange- 
ments of  the  stomach  and  alimentary  tract,  or  from 
the  mucous  and  salivary  glands,  or  from  the  fermen- 
tation or  decomposition  of  food  about  the  teeth, 
there  is  another  agent  which  is  supposed  to  play  an 
important  part  in  the  extension  of  caries,  viz.,  a  vege- 
table parasite — a  fungus  —  found  in  the  interstices, 
furrows,  and  depressions  of  neglected  teeth,  but  most 
abundantly  in  cavities  of  decay.  It  is  not  claimed 
that  this  fungus  originates  decay,  but  that  it  becomes 
an  active  agent  in  the  destructive  process  when  once 
a  loss  of  substance  has  been  caused  in  the  enamel  — 
its  filaments  penetrating  the  minute  chinks,  excava- 
tions, and  orifices  caused  by  disintegration,  and 
opening  the  way  for  the  entrance  of  chemically 
destructive  agents.  The  development  of  this  fungus 
seems  to  be  favored  by  an  acid  condition  of  the 
mouth.  Treatment,  therefore,  which  corrects  the 
acidity  lessens  the  danger.  Antacid  washes,  espe- 
cially washes  or  powders  containing  soap,  hinder  the 
development  of  the  parasitic  vegetation. 

Whatever  may  be  said  of  the  deleterious  efi"ects  of 
tobacco  upon  the  general  system,  it  has  not  been 
proved  to  have  any  influence  in  the  production  of 
caries,  although  the  discoloration  which  results  from 


Il6  THE   MOUTH  AND    THE    T^ETH. 

its  continued  use  detracts  markedly  from  the  appear- 
ance of  the  teeth.  In  this  connection  it  may  be  men- 
tioned that  the  use  of  a  clay  pipe  produces  a  rapid 
abrasion  of  the  teeth  between  which  it  is  held,  and 
that  short  pipes  are  charged  with  the  development 
of  cancerous  affections  of  the  tongue  and  lips. 

Sugar  and  confections  exercise  no  directly  injurious 
effects  upon  the  teeth,  but  when  taken  in  excess  do 
produce  an  acid  condition  of  the  stomach  unfavor- 
able to  the  health  of  the  mouth,  and  when  left  in  the 
interstices  of  the  teeth  rapidly  undergo  an  acid  fer- 
mentation, resulting  in  a  product  capable  of  acting 
very  injuriously  upon  tooth-structure.  Particles  of 
candy  remaining  between  the  teeth  will,  in  a  single 
night,  produce  demonstrable  mischief. 

The  progress  of  decay  of  the  teeth  is  as  varied  in 
different  individuals  and  at  different  times  as  is  the 
character  of  the  disintegration.  It  proceeds  some- 
times insidiously  and  slowly,  and  again  with  wonder- 
ful rapidity;  sometimes  announcing  its  ravages  by  a 
sensitiveness  of  the  exposed  dentine  to  sweets  and 
acids  and  to  changes  of  temperature,  and  at  other 
times  giving  no  notice  of  its  presence  until  a  com- 
plete exposure  of  the  pulp  has  been  made. 


CHAPTER    XVII. 

TOOTHACHE EXTRACTION  —  HEMORRHAGE. 

PAIN  or  discomfort  in  or  about  a  tooth  may  arise 
from  a  variety  of  causes.  In  perfectly  sound 
teeth  rhciumatism  sometimes  causes  distressing  pain, 
which  may  be  located  in  one  or  two  teeth,  or  involve 
half  of  a  jaw,  or  even  the  entire  jaw.  Neuralgia, 
originating  as  it  does  very  frequently  in  diseased 
teeth,  may  have  its  origin  elsewhere  and  manifest  it- 
self in  teeth  which  are  perfectly  sound.  Valuable 
teeth  are  often  sacrificed  from  this  cause.  Pain 
is  frequently  experienced  in  a  tooth  which  is  only 
sympathetically  affected.  These  facts  have  been  ex- 
plained in  the  chapter  on  "The  Nervous  Relations 
of  the  Teeth."  A  recession  of  the  gums  and  alve- 
olar process  from  about  the  neck  of  a  tooth,  ex- 
posing the  cementum,  gives  rise  in  some  cases  to  a 
dull  and  annoying  ache.  Particles  of  tartar  which 
have  found  their  way  between  the  gum  and  the  alve- 
olar process  may  occasion  soreness  and  distress,  if  not 
acute  pain.  The  disease  known  as  exostosis^  which 
may  be  described  as  an  unnatural  enlargement  of  the 

117 


Il8  THE  MOUTH  AND   THE    TEETH. 

root  of  a  tooth,  is  often  the  cause  of  constant  un- 
easiness, and  sometimes  of  distressing  pain.  In  some 
cases  there  is  a  peculiar  deposit  in  the  palp  of  a 
tooth  of  granules  of  bone-like  material  which  causes 
severe  neuralgic,  generally  paroxysmal,  pain,  some- 
times located  in  the  tooth  (which  yet  gives  no  evi- 
dence of  trouble,  either  by  soreness,  discoloration, 
or  decay),  and  sometimes  reflected  to  the  eye,  ear, 
scalp,  or  elsewhere.  The  death  of  the  pulp  in  a  tooth — 
the  result  of  a  fall,  blow,  or  other  accidental  or  vol- 
untary violence,  or  from  some  unexplained  cause  — 
becomes  the  occasion  of  unbearable  pain  when  the 
products  of  its  decomposition  are  confined  in  the  pulp 
cavity.  Some  teeth,  in  which  a  cavity  of  decay  has 
exposed  the  dentine,  become  exceedingly  sensitive  to 
the  influence  of  irritating  agents.  In  such  cases  sweets 
or  acids  taken  into  the  mouth,  or  cold  or  hot  drinks, 
or  even  the  secretions  of  the  mouth,  will  occasion 
pain. 

Chief  in  frequency,  however,  of  the  causes  of  pain 
in  a  tooth  is  the  absolute  or  approximate  exposure 
of  the  pulp,  which,  as  has  been  previously  explained, 
is  located  in  a  cavity  having  the  general  form  of 
the  tooth  and  protected  on  all  sides  by  its  walls. 
When  by  the  agency  of  decay  the  overlying  floor  of 
the  cavity  becomes  so  thin  as  to  be  permeable,  the 
result  is  an  irritation  of  the  delicate  and  exquisitely 
organized  pulp,  and  consequently  acute  pain.     When 


TO  O  THA  CHE  —  EXTRA  CTION—  HEMORRHA  QE.   1 1 9 

the  protecting  wall  of  dentine  has  been  so  far  disin- 
tegrated as  to  expose  the  pulp,  the  latter  is  liable  to 
constant  irritation  by  contact  with  food  or  drinks, 
with  the  secretions  of  the  mouth,  or  even  with  the 
atmospheric  air.  A  small  defect  in  the  continuity  of 
the  dentine  is  likely  to  result  in  greater  distress 
than  would  ensue  from  a  complete  exposure,  for  the 
reason  that  in  the  latter  case  the  swollen  pulp  has  room 
for  its  enlargement,  while  in  the  former  the  unyielding 
walls  of  the  tooth  confine  it.  The  pressure  makes 
manifest  every  pulsation  of  the  heart,  causing  that  form 
of  anguish  known  as  "jumping  toothache."  Those 
who  have  experienced  this  pain  need  no  description  of 
it ;  those  who  have  not,  would  do  well  to  avoid  a  prac- 
tical acquaintance  with  it. 

Still  another  form  of  pain  in  connection  with  teeth 
is  that  which  is  occasioned  by  an  inflammation  of  the 
membrane  surrounding  the  roots  and  investing  the 
sockets.  This  affection  is  known  by  the  name  oi peri- 
odontitis —  inflammation  about  a  tooth.  The  con- 
dition may  be  either  acute  or  chronic,  and  may  be 
the  result  of  the  continued  influence  of  neuralgia,  gout, 
or  rheumatism  ;  of  the  irritation  of  deposits  of  tartar 
between  a  tooth  and  its  socket  \  of  mercurial  poison- 
ing, or  of  one  of  the  eruptive  fevers  (measles,  scarlet- 
fever,  small-pox,  etc.);  of  an  attack  of  scurvy;  of  de- 
generative changes  from  age  or  other  causes,  either  in 
the  membrane  itself  or  in  the  roots  of  the  teeth ;  of 


I20  THE  MOUTH  AND    THE    TEETH. 

false  (premature)  occlusion  of  a  tooth  in  mastication, 
either  because  of  its  position  or  of  an  undue  promi- 
nence of  a  filling  on  a  crown  surface,  and  of  mechan- 
ical violence  —  accidental,  voluntary,  or  from  the  in- 
judicious use  of  the  mallet  in  filling,  or  from  exces- 
sive wedging  to  separate  the  teeth  for  examination  or 
operation. 

The  acute  or  active  form  may  be  the  result  of  **a 
cold  settling  in  the  jaws,"  as  it  is  commonly  expressed, 
and  generally  subsides  after  a  few  hours  or  days  of 
discomfort.  The  most  common  and  the  most  severe 
form  of  periodontitis,  however,  is  that  which  is  as- 
sociated with  disease  or  death  of  the  pulp  in  a  tooth. 
Teeth  in  which  an  unsuccessful  attempt  has  been  made 
to  save  an  exposed  pulp  by  "capping,"  as  well  as 
those  in  which  the  pulp  has  been  devitalized  but  its 
complete  removal  not  accomplished,  are  liable  to  peri- 
odontitis, especially  during  sudden  changes  in  the 
weather,  or  as  a  result  of  a  disturbance  of  health  in 
the  individual.  Periodontitis  usually  commences 
with  a  scarcely  noticeable  uneasiness  in  the  tooth, 
but  deepens  into  a  dull,  heavy,  sometimes  throb- 
bing, persistent  pain.  From  the  swelling  of  its  in- 
vesting membrane,  the  tooth  projects  beyond  its 
fellows,  compelling  a  discontinuance  of  all  masticatory 
efforts  for  the  time  being.  The  pain  increases  in  in- 
tensity, and  is  accompanied  by  more  or  less  swelling 
of  the  face.     Unless  the  diseased  action  be  arrested  by 


TO  O  THA  CHE  —  EXTRA  CTION—  HE  MORE  HA  GE.   121 

treatment,  an  abscess  forms  at  the  root  of  the  tooth, 
the  resulting  pus  generally  finding  its  way  to  the  sur- 
face of  the  gum  opposite  the  abscess,  or  at  some  other 
point  in  the  mouth,  forming  what  is  popularly  known 
as  "  gum-boil."  After  the  discharge  of  the  pus  the 
pain  subsides,  and  the  swelling  gradually  disappears. 
But  the  disease  is  not  cured,  and  after  a  longer  or 
shorter  period,  depending  on  various  circumstances  — 
notably  on  the  good  or  the  ill  health  of  the  individual 
—  there  will  be  a  recurrence  of  the  abscess.  If  this  is 
repeated  too  often,  the  bony  socket  of  the  tooth  be- 
comes affected,  the  sockets  of  adjoining  teeth  partici- 
pate in  the  trouble,  the  teeth  lose  their  vitality  and 
drop  out,  and  sometimes  necrosis  (death)  of  a  portion 
of  the  jaw  follows.  Sometimes  the  pus,  instead  of  find- 
ing exit  near  the  affected  tooth,  burrows  among  the 
tissues,  and  makes  an  outlet  (called  a  "sinus")  for 
itself  at  a  distant  point  inside  or  outside  of  the  mouth, 
not  infrequently  producing  disfiguring  scars  on  the 
face.  When  the  symptoms  indicate  periodontitis, 
treatment  should  be  instituted  with  a  view  to  pre- 
vent the  formation  of  an  abscess,  or,  if  this  effort  fails, 
to  influence  it  to  open  at  a  desirable  point  —  inside 
of  the  mouth,  and  not  upon  the  face.  Domestic  treat- 
ment of  this  affection  is  usually  wrongly  directed,  and 
that  prescribed  by  the  average  general  practitioner  of 
medicine  is  almost  equally  at  fault.  The  best  pos- 
sible advice  which  can  be  given  here  is  to  consult  an 
II 


122  THE  MOUTH  AND    THE    TEETH. 

intelligent  practitioner  of  dentistry  at  an  early  stage 
of  the  trouble,  at  which  time  it  can  frequently  be 
aborted. 

For  the  relief  of  toothache  from  approximate  or 
actual  exposure  of  the  pulp,  an  application  to  the 
cavity  of  decay  of  a  little  ball  of  cotton  saturated  with 
oil  of  cloves,  oil  of  peppermint,  or  phenol  sodique 
in  full  strength,  is  perhaps  the  best  amateur  treatment 
where  the  cavity  is  easily  reached.  In  other  cases, 
holding  in  the  mouth  phenol  sodique  diluted  with 
from  three  to  six  times  its  bulk  of  water  will  frequently 
alleviate  the  pain.  But  it  must  be  remembered  that, 
if  the  pulp  is  nearly  or  quite  exposed,  a  recurrence  of 
the  pain  is  probable  at  any  moment.  For  permanent 
relief  the  only  efficient  plan  is  to  secure  the  services 
of  a  dentist.  In  the  case  of  a  child  suffering  from 
toothache  in  a  temporary  tooth,  the  difficulty  of  ap- 
plying local  sedatives  directly  to  the  cavity  of  decay  is 
vastly  increased  by  the  fear  (often  well  founded)  that 
the  affection  will  be  aggravated  by  the  lack  of  skill  in 
the  amateur  operator,  and  by  the  exceeding  amount 
of  the  salivary  secretion,  making  it  difficult  even  for 
an  expert  to  operate  satisfactorily.  The  disinclination 
to  have  in  the  mouth  anything  which  tastes  or  smells 
unpleasant,  or  which  produces  any  disagreeable  sen- 
sation upon  the  mucous  membrane,  is  a  difficulty  in 
the  way  of  using  such  remedies  as  have  been  sug- 
gested.    In  these  cases  holding  warm  milk,  or  even 


TO  O  THA  CHE  —  EXTRA  CTION—  HEMORRHA  GE.   1 2 3 

warm  water,  in  the  mouth  will  frequently  give  tem- 
porary relief. 

It  should  be  remembered  that  a  tooth  which  has 
ached  once  will  be  likely  to  ache  again,  and  an  en- 
deavor should  be  made  to  prevent  a  second  attack  in 
the  same  tooth  by  securing  professional  advice. 

It  is  seldom  that  the  extraction  of  a  tooth  becomes 
a  necessity.  Thousands  of  teeth  are  sacrificed  through 
impatience,  the  result  of  the  pain  which  ought  to  have 
been  avoided  by  timely  attention,  and  which  might 
have  been  alleviated  and  the  teeth  preserved. 

The  facility  afforded  for  the  painless  extraction  of 
teeth  by  the  use  of  nitrous  oxide  gas  leads  to  the  need- 
less, wanton,  wicked  sacrifice  of  useful  organs  —  to 
losses  which  can  never  be  made  good.  The  willing- 
ness of  many  persons  to  part  with  valuable  teeth  rather 
than  take  a  little  trouble  and  incur  a  small  expense 
for  their  preservation,  is  an  evidence  of  ignorance  and 
of  a  readiness  to  submit  to  mutilation  of  the  mouth 
as  remarkable  as  general. 

There  is  urgent  need  of  a  popular  awakening  to 
the  fact  that  wilful  neglect  of  the  health  of  any  por- 
tion of  the  body  is  criminal ;  that  such  neglect  differs 
only  in  degree  from  suicide.  The  preservation  of  the 
integrity  of  the  physical  organism  and  of  the  vital 
forces,  and  the  restoration  of  diseased  or  wounded 
members  whenever  possible,  may  be  said  to  be  the 
leading  principle  alike  of  surgery,  of  medicine,  and 


of  dentistry.  It  should  be  the  ambition  of  every  in- 
dividual to  retain  as  long  as  possible  each  organ  and 
faculty  of  body  and  of  mind.  But  when  it  becomes 
desirable  as  a  choice  of  evils  to  sacrifice  a  tooth,  it  is 
a  weakness  and  a  folly  to  allow  it  to  remain  through 
dread  of  the  brief  pain  accompanying  extraction. 
If  its  room  is  better  than  its  company,  and  its  dis- 
placement is  demanded  for  conservative  reasons,  the 
sooner  it  is  removed  the  better,  both  for  the  health  of 
its  neighbors  and  for  the  comfort  of  its  owner. 

The  bleeding  which  follows  the  extraction  of  a 
tooth  is  usually  of  short  duration  and  ceases  without 
requiring  any  attention.  In  very  exceptional  cases  it 
may  be  so  profuse  and  long-continued  as  to  demand 
treatment.  The  anxiety  of  the  patient  to  have  it 
cease  leads  sometimes  to  such  constant  interference 
as  to  effectually  prevent  natural  cessation  by  the  clot 
which  would  otherwise  form  in  the  socket.  The  first 
injunction,  therefore,  in  such  cases  is,  do  not  disturb 
the  clot.  If,  in  spite  of  such  negative  attention,  the 
bleeding  continues,  resort  may  be  had  to  the  applica- 
tion of  astringents  or  styptics,  such  as  alum,  tannin, 
catechu,  kino,  krameria,  phenol  sodique,  or  remedies 
which  act  mechanically,  such  as  powdered  resin,  burnt 
cork,  spider' s-web,  etc.  Of  the  various  astringents, 
tannin  is  perhaps  the  most  efficacious.  Either  that  or 
powdered  alum  may  be  applied  to  the  socket  of  the 
tooth  on  a  small  pledget  of  cotton.     If  these  remedies 


TO  O  THA  CHE  —  EXTRA  CTION—  HEMORRHA  GE.   125 

are  not  available,  cobweb,  which  can  generally  be  pro- 
cured without  much  difficulty,  may  be  rolled  into  a 
small  pellet  or  ball  and  carried  into  the  bleeding  sccket 
by  a  match-stick  or  piece  of  stout  broom-corn.  If 
the  case  be  a  stubborn  one,  and  refuses  to  yield  to 
such  applications,  pressure  may  be  added.  The  little 
pledget  of  cotton  carrying  the  tannin  or  other  styptic 
should  be  dropped  into  the  socket,  which  may  then 
be  compressed  by  a  V-shaped  saddle  (made  of  cork  or 
wood)  so  as  to  clamp  the  margins  of  the  gum,  and  be 
held  in  place  by  the  opposing  teeth  or  jaw,  assisted, 
if  need  be,  by  a  bandage  holding  the  jaws  together. 
To  divert  the  circulation  to  other  parts  of  the  body, 
hot  foot-baths  may  be  resorted  to,  and  a  sitting  in- 
stead of  a  recumbent  posture  assumed,  that  the  law 
of  gravitation  may  also  conduce  to  the  desired  result. 
In  exceptionally  extreme  cases,  when  such  measures 
as  have  been  indicated  fail,  further  treatment  should 
be  instituted  by  the  dentist  or  physician,  and  should 
include  systemic  medication. 
II* 

-1.    o^A     nA^-^^ 


CHAPTER    XVIII. 

HYGIENE    OF   THE   MOUTH. 

THE  comfort  of  a  pure  breath  and  wholesome  saliva, 
the  agreeable  effect  produced  upon  others  by  the 
exhibition  of  a  clean  and  healthy  mouth,  the  advan- 
tage of  the  teeth  in  vocalization,  the  favorable  im- 
pression made  upon  the  general  health  by  the  ability 
thoroughly  to  masticate  the  food,  exemption  from  the 
suffering  which  would  be  caused  by  diseased  organs, 
and  the  possibility  of  the  preservation  and  usefulness 
of  the  teeth  till  advanced  life,  are  reasons  sufficient, 
it  would  be  thought,  to  induce  every  one  to  pay  that 
attention  to  the  health  of  the  mouth  which  would 
secure  such  results.  As  far  as  the  teeth  are  concerned, 
their  liability  to  decay  and  the  fact  that,  unlike  other 
portions  of  the  body,  they  are  not  endowed  with  the 
power  to  repair  injury  or  replace  lost  tissue,  so  that 
when  decay  has  destroyed  any  portion  of  their  struct- 
ure there  is  no  possibility  of  its  restoration,  are  most 
urgent  reasons  why  they  should  receive  intelligent  and 
earnest  care. 

In  the  chapters  on  "  Salivary  Calculus  "  and  "  De- 

126 


HYGIENE    OF   THE  MOUTH.  12/ 

cay  of  the  Teeth"  it  has  been  shown  that  the  accu- 
mulation of  tartar  about  the  necks  of  the  teeth  and 
the  retention  of  food  and  other  matters  in  their  de- 
pressions and  between  their  contiguous  surfaces,  there 
to  undergo  fermentation  and  decomposition,  are  the 
principal  exciting  causes  of  diseased  gums,  loosened 
teeth,  and  decay.  It  follows,  therefore,  that  such  de- 
posits should  be  removed  before  they  have  had  an 
opportunity  to  work  mischief.  There  is  no  ques- 
tion that  the  one  great  essential  to  a  healthy  mouth  is 
cleanliness.  In  fact,  few  even  of  those  who  pride 
themselves  upon  the  care  which  they  bestow  upon 
their  dental  organs  give  to  them  the  attention  which 
their  value  would  justify.  Many  otherwise  intelligent 
people  fail  to  appreciate  the  importance  of  taking 
due  care  of  their  teeth  until  compelled  by  suffering 
to  do  so.  Then,  when  the  demand  has  become  im- 
perative, their  chief  thought  seems  to  be  not  how  best 
to  prevent  further  mischief  and  to  retain  what  is  left  of 
their  dental  organs  in  as  perfect  a  condition  as  pos- 
sible, but  how  imm.ediate  relief  can  be  secured,  or  else 
how  painless  extraction  can  be  effected.  It  must  not 
be  forgotten  that  decay  is  not  the  only  enemy  of  the 
teeth.  The  absorption  of  the  gums  and  sockets  caused 
by  the  presence  of  tartar  is  a  liability  which,  though 
not  absolutely  confined  to  teeth  which  are  neglected, 
is  yet  a  danger  specially  threatening  such.  This  re- 
sult might  in  a  majority  of  instances  be  prevented  by 


128  THE  MOUTH  AND    THE    TEETH. 

intelligent  care  —  recession  of  the  gums  or  absorpjtion 
of  the  sockets  rarely  occurring  in  mouths  that  are 
habitually  kept  pure. 

On  the  other  hand,  many  scrupulously  careful  people 
bring  about  the  evils  which  they  seek  to  avert,  by  im- 
proper methods  and  appliances.  Much  mischief  is 
wrought  by  the  use  of  unsuitable  brushes  and  injudi- 
cious brushing;  by  the  use  of  tooth-powders  and 
mouth-washes  made  in  ignorance  of  the  purposes  to 
be  subserved  by  their  employment,  and  likely  to  do 
harm,  either  because  of  their  chemical  action  upon 
tooth-substance,  their  unfavorable  influence  upon  the 
health  of  the  gums,  or  because  of  their  containing 
ingredients  likely  to  be  deposited  about  the  necks  of 
the  teeth  and  thus  cause  the  absorption  of  the  gums 
and  alveolar  processes.  Simple  measures  regularly 
employed  are  sufficient  for  healthy  mouths.  In  dis- 
eased conditions  the  wash  or  powder  to  be  employed 
should  be  prescribed  by  an  intelligent  dentist.  Patent 
nostrums  and  advertised  powders  and  washes  should 
be  avoided.  Any  wash  that  is  recommended  for 
whitening  the  teeth  is  either  incapable  of  accom- 
plishing what  is  claimed  for  it  or  does  so  at  the 
expense  of  the  integrity  of  the  enamel.  The  ha- 
bitual use  of  astringent  washes  or  powders,  so  far 
from  being  conducive  to  the  health  of  the  gums,  is 
injurious.  For  certain  purposes  such  dentifrices  are 
of  service,  but  their  use  should  be  discontinued  as 


HYGIENE    OF   THE   MOUTH.  1 29 

soon  as  the  object  for  which  they  are  employed  has 
been  accomplished.  Strongly  alkaline  washes  are  also 
injurious.  Washes  or  powders  containing  alum,  cream 
of  tartar,  charcoal,  ground  barks,  or  acids  of  any  de- 
scription, are  injurious  either  because  of  a  chemical 
action  upon  the  teeth  or  because  their  insoluble  in- 
gredients are  apt  to  insinuate  themselves  under  the 
margins  of  the  gums.  Tooth-powders  containing 
excessively  gritty  or  abrasive  ingredients,  or  even 
those  of  ordinary  abrasive  power  not  sufficiently  fine, 
do  injury  by  roughening  instead  of  polishing  the  en- 
amel surfaces  of  the  teeth.  Perhaps  there  is  no  agent 
in  common  use  for  cleansing  the  teeth  worthy  of  such 
utter  condemnation  as  powdered  charcoal.  The  re- 
sults of  its  employment  are  exceedingly  pernicious; 
the  harsh,  insoluble  particles  force  themselves  between 
the  gums  and  the  teeth,  creating  irritation,  soreness, 
and  inflammation  of  the  tissues,  and  form  nuclei  for 
the  dej)osit  of  tartar,  resulting  in  the  absorption  of 
the  alveolar  processes,  and  in  the  loosening  and  loss 
of  the  teeth.  Its  continued  use  also  causes  the  gums 
to  assume  a  tattooed  appearance,  like  that  whick 
India-ink  produces  when  pricked   into  the  flesh. 

A  mouth-wash  may  be  anodyne,  astringent,  disin- 
fectant, stimulant,  or  tonic,  according  to  the  indica- 
tions ;  but,  if  the  secretions  are  natural  and  the  gums 
healthy,  the  wash  should  merely  be  pleasant  to  the 
taste,  agreeable  in  odor,  and  slightly  antacid  or  sapo- 

I 


130  THE  MOUTH  AND    THE    TEETH. 

naceous  —  not  astringent.  A  tooth-powder,  for  a 
healthy  condition  of  the  mouth  and  teeth,  should  be 
merely  a  mechanical  agent,  possessing  a  hardness  suf- 
ficient for  the  removal,  without  liability  to  injure  the 
enamel,  of  slight  accumulations  of  food  and  tartar. 
It  should  be  soluble  in  the  fluids  of  the  mouth,  and 
for  most  persons  antacid.  In  mouths  that  are  already 
alkaline  —  most  likely  to  occur  after  middle  life  —  the 
antacid  ingredients  may  advantageously  be  omitted, 
and  a  powder  employed  possessing  only  mechanical 
qualities. 

It  is  safe  to  affirm  that  a  very  large  majority  of 
persons  err  in  the  selection  of  a  tooth-brush.  Most  of 
the  brushes  in  the  market  are  too  stiff  and  too  large. 
The  habitual  use  of  such  brushes  is  attended  with  ill 
results.  Again,  those  who  are  most  solicitous  to  secure 
perfect  cleanliness  of  the  teeth  are  apt  to  err  decidedly 
in  a  too  vigorous  use  of  the  brush.  Many  sets  of  teeth 
have  been  ruined  by  too  much  or  injudicious  brush- 
ing. Skill  and  not  force,  faithfulness  and  not  muscle, 
are  required  to  secure  the  best  results.  Most  persons 
scrub  the  outer  surfaces  of  the  teeth,  as  if  to  clean  by 
scouring  or  friction  were  the  object  in  using  a  brush. 
A  very  7)ioderate  application  of  a  proper  brush  with  a 
gentle  frictional  powder  is  sufficient  for  the  external 
surfaces  of  the  teeth,  and  is  desirable  in  order  to  pre- 
vent the  tendency  to  unsightly  discolorations,  but  as  a 
prevention  of  decay  is  the  least  useful  mode  of  brush- 


HYGIENE    OF   THE  MOUTH.  131 

ing.  Indeed,  if  the  cleansing  process  is  carried  no 
further,  this  style  of  brushing  does  perhaps  more  harm 
than  good,  as  it  rubs  particles  of  food  and  stringy  mucus 
in  between  the  teeth,  and  allows  them  to  remain  just 
where  they  are  capable  of  producing  the  greatest  mis- 
chief. The  surfaces  of  the  teeth  which  are  exposed 
to  the  movements  of  the  tongue,  lips,  and  cheeks, 
being  thereby  protected,  do  not  especially  need  brush- 
ing, except  to  remove  stains,  while  the  interstices, 
interspaces,  fissures,  depressions,  and  cavities  are  ex- 
posed to  the  deleterious  action  of  the  fermenting 
materials  which  naturally  lodge  there,  to  which  are 
added  the  reinforcements  carried  by  crosswise  brush- 
ing. It  should  be  remembered  that  the  removal  of 
accumulations  of  food  or  mucus  from  the  depressions 
in  the  bicuspids  and  molars  and  from  between  the 
teeth  is  the  essential.  The  brush  should  be  mod- 
erately soft,  the  bristles  long  and  elastic  and  of 
uneven  lengths,  so  as  to  facilitate  their  introduction 
between  the  teeth.  The  upper  teeth  should  be 
brushed  downward  and  the  lower  teeth  upward,  both 
on  the  outer  and  inner  surfaces,  thus  avoiding  crowd- 
ing the  gums  from  off  the  necks  of  the  teeth  while 
tending  to  the  dislodgment  of  any  deposits  between 
them.  The  articulating  faces  of  the  teeth  should  be 
brushed  with  the  same  care  as  the  ©ther  surfaces  — 
backward  and  forward  and  from  side  to  side  over  the 


132  THE  MOUTH  AND    THE    TEETH. 

grinding  surfaces  of  the  molars,  so  as  to  cleanse  all 
the  depressions. 

Once  daily  is  quite  often  enough  to  use  a  powder, 
and  the  best  time  is  just  before  retiring.  During  the 
waking  hours  the  various  movements  of  the  tongue 
and  muscles  of  the  mouth  in  speech  and  otherwise, 
the  constant  salivary  secretion  and  the  mastication  of 
food,  all  tend  to  prevent  the  chemical  changes  which 
during  sleep  take  place  without  hindrance.  The 
morning  cleansing  may  be  properly  performed  with 
the  aid  of  a  little  pure,  mild  soap,  such  as  old  Castile, 
or  a  reliable  tooth-soap  made  expressly  for  the  pur- 
pose; the  latter  will  be  all  the  more  efficient  if  it 
contain  an  antiseptic  such  as  creasote,  carbolic  acid, 
or  salicylic  acid.  After  meals  it  will  be  sufficient  to 
use  tepid  water  to  which  has  been  added  a  few  drops 
of  spirit  of  ammonia,  or  a  little  bicarbonate  of  soda, 
or  lime-water  —  simply  to  neutralize  any  acidity. 
These  after-meal  cleansings  should  not  involve  a  too 
vigorous  use  of  the  brush  —  merely  a  skilful  dislodg- 
ment  of  adhering  or  impacted  food  is  required.  In 
fact,  if  the  use  of  the  brush  leads  to  the  scrubbing 
process,  it  would  better  be  dispensed  with,  substi- 
tuting a  thorough  rinsing  of  the  mouth  with  tepid 
water,  made  slightly  antacid,  as  suggested  above. 
A  muscular  styk  of  brushing  five  times  daily  will  be 
injurious  to  the  gums,  if  not  to  the  teeth. 

During  the  period  occupied  by  the  shedding  and 


HYGIENE    OF   THE  MOUTH.  1 33 

replacement  of  the  temporary  teeth  —  say  from  five 
to  fifteen  years  of  age  —  it  is  difficult  to  keep  the 
teeth  clean  or  the  mouth  sweet  and  healthy.  It  is 
advantageous  during  this  time,  indeed  at  any  period 
of  life  when  an  acid  condition  of  the  mouth  is  recog- 
nized, to  use  after  the  evening  brushing  a  small  quan- 
tity of  precipitated  chalk,  nibbing  it  into  the  inter- 
stices of  the  teeth  with  the  finger  and  allowing  it  to 
remain.  The  quantity  need  not  be  enough  to  be 
unpleasant ;  as  much  as  would  adhere  to  the  end  of 
a  moistened  finger  is  sufficient  to  counteract  any 
acidity  during  the  night. 

The  use  of  a  quill  toothpick  after  meals  to  dislodge 
particles  of  food  from  between  the  teeth  is  advisable, 
as  is  also  the  use  of  a  strand  of  waxed  floss  silk  passed 
between  them  at  least  once  daily. 

Such  is  the  care  suggested  by  the  inestimable  value 
of  the  teeth,  and  by  their  increasing  tendency  to 
early  decay ;  but  such  care  can  hardly  be  hoped  for 
until  the  public  realize  that  to  lose  a  tooth  is  a  real 
misfortune,  to  extract  one  unnecessarily  a  crime.  A 
perfect  denture  !  How  few  understand  the  signifi- 
cance of  the  term  !  A  set  of  thirty-two  teeth  in  two 
unbroken  arches  —  not  one  missing,  not  even  one  de- 
cayed tooth  —  the  beau  ideal  of  dental  perfection. 
But  the  loss  of  a  tooth,  except  in  the  front  of  the 
mouth,  is  not  considered  a  serious  matter  by  most 
persons,  and  the  extent  of  the  disaster  is  not  appre- 
12 


134  THE  MOUTH  AND    THE    TEETH. 

ciated  perhaps  for  years  afterwards.  Unquestionably, 
if  all  the  various  offices  of  the  teeth  were  fully  com- 
prehended, the  really  small  amount  of  attention  which 
is  required  would  be  cheerfully  bestowed. 

As  a  frictional  powder,  precipitated  chalk  is  a  safe 
and  generally  efficient  agent.  Where  this  is  found 
insufficient  to  prevent  the  staining  or  discoloration 
of  the  teeth,  it  may  properly  be  combined  in  various 
1  proportions  with  the  inside  of  the  cuttle-fish  bone,  or 
with  a  smaller  quantity  of  very  fine ly-powdered  "^Mvaico. 
stone.  In  case  the  mouth  is  habitually  alkaline,  pow- 
dered orris-root  combined  with  the  cuttle-fish  bone  or 
pumice  as  above  may  be  substituted  for  the  chalk. 

Mouth-washes  should  be  used  with  reference  to  the 
existing  conditions.  Lime-water  is  recommended, 
in  full  strength,  or  more  or  less  diluted  where  the 
mucous  secretions  are  viscid  or  fetid ;  where  the  ani- 
mal constituents  are  in  excess  of  the  earthy  in  the 
composition  of  the  teeth ;  where  there  is  special  sen- 
sitiveness either  of  the  dentine  or  of  denuded  roots, 
and  where  an  antacid  is  needed  to  neutralize  the 
action  of  acid  medicines  upon  the  teeth.  In  those 
cases  where  there  is  an  evident  tendency  to  rapid 
disintegration  of  tooth-structure,  the  daily  use  of 
lime-water  as  a  mouth-wash  is  attended  with  bene- 
ficial results.  Its  unpleasant  taste  can  be  disguised 
by  the  addition  of  a  small  quantity  of  bruised  licorice- 
root.     The  addition  of  a  few  drops  of  spirit  of  am- 


\ 


HYGIEXE    OF   THE   MOUTH.  1 35 

monia  to  a  tumblerful  of  water  makes  a  convenient 
and  efficient  remedy  for  use  on  the  brush,  or  as  a 
mouth-wash  where  an  antacid  is  indicated.  For  like 
purposes  a  half- teaspoon ful  or  less  of  bicarbonate  of 
soda  to  a  glass  of  water  is  also  efficient. 

The  injurious  action  of  acid  medicines  upon  the 
teeth  should  be  counteracted  by  rinsing  the  mouth 
thoroughly  with  either  of  the  foregoing  washes  imme- 
diately after  swallowing  the  medicine.  This  immedi- 
ate neutralization  of  the  acid  is  much  more  trustworthy 
than  the  use  of  a  tube,  through  which  the  medicine  is 
often  directed  to  be  taken,  and  is  advisable  even  in 
addition  to  the  use  of  the  tube. 

The  peculiarly  disagreeable  sensation  described  as 
having  the  teeth  *'  set  on  edge,"  which  results  from 
taking  acid  fruits,  foods,  drinks,  or  medicines  into 
the  mouth,  is  caused  by  the  action  of  the  acid  upon 
the  enamel,  perceptibly  roughening  its  surface.  This 
effect  is  injurious,  and  if  frequently  induced  cannot 
but  prove  destructive  even  to  perfectly  sound  teeth; 
being,  however,  specially  objectionable  in  the  case 
of  teeth  which  have  been  filled,  destroying  the  in- 
tegrity of  fillings  by  eroding  the  tooth-substance 
around  their  margins. 

The  tincture  of  krameria,  mixed  with  an  equal 
quantity  of  good  eau  de  Cologne  and  diluted  with 
water,  makes  an  elegant  and  delightful  astringent 
mouth-wash.      Tincture    of    myrrh,    so    often    pre- 


136  THE  MOUTH  AND    THE    TEETH. 

scribed,  is  of  questionable  value  as  a  mouth-wash, 
from  the  fact  that  the  dilution  of  the  tincture  occa- 
sions a  precipitation  of  the  resin  of  which  it  is  made 
about  the  necks  of  the  teeth,  aggravating  rather  than 
alleviating  spongy  conditions  of  the  nwgins  of  the 
gums.  An  excellent  mouth-wash  for^^ongy  and 
bleeding  gums,  to  be  used  after  the  remd3^al  of  the 
exciting  causes,  is  made  by  combining  one  drachm 
of  tannin,  two  drachms  of  chlorate  of  potash,  and  a 

-  pint  of  boiling  water.  A  teaspoonful  of  the  tincture 
of  calendula  to  a  goblet  of  water  makes  a  pleasant 
and  efficient  mouth-wash  for  use  after  the  removal 
of  deposits  about  the  teeth,  or  after  extraction  of  teeth. 
Perhaps  no  single  article  is  more  useful  as  a  wash 
in  various  conditions  of  the  mouth  than  phenol 
sodique  —  a  preparation  made  from  tar.  It  is  an 
antacid,  an  astringent,  a  sedative,  a  styptic,  an  anti- 
septic, and  a  disinfectant.  As  a  wash  for  the  mouth 
■J    it  is  highly  useful  (when  there  are  no  local  exciting 

^  mechanical  causes)  in  that  class  of  cases  of  soft, 
spongy,  swollen  gums  which  bleed  at  the  slightest 
touch.  It  checks  excessive  bleeding  after  extrac- 
tion, and  relieves  the  subsequent  soreness  of  the 
gums.  It  gives  prompt  relief  to  the  distressing  pains 
which  sometimes  follow  extraction;  corrects  unpleas- 
antness of  the  breath  caused  by  decayed  teeth  or  by 
unhealthy  secretions  of  the  mouth,  while  its  antacid 
and  antiseptic  properties  make  it  a  valuable  agent  in 


HYGIENE    OF   THE   MOUTH.  1 37 

correcting  acidity  and  preventing  putrefaction.  It 
may  be  used,  to  meet  varying  indications,  diluted 
more  or  less  from  half  a  teaspoonful  to  a  tablespoon- 
ful  in  a  tumblerful  of  water. 

These  suggestions  are  not  intended  to  encourage  a 
dependence  upon  any  of  the  articles  specified  so  much 
as  to  discourage  the  use  of  unsuitable  dentifrices  and 
washes,  and  especially  of  all  advertised  or  secret  prep- 
arations ''warranted  to  harden  the  gums  and  whiten 
the  teeth." 

As  suggested  in  previous  chapters/  more  than  usual 
care  of  the  mouth  is  required  during  sickness.  It  will 
also  be  recognized  that  teeth  need  care  in  proportion 
as  they  are  poorly  organized  or  irregularly  arranged. 

The  treatment  of  unhealthy  conditions  of  the  mouth, 
as  shown  in  a  predisposition  to  decay  of  the  teeth, 
must,  to  be  successful,  be  systemic  as  well  as  local ; 
but,  fortunately,  that  treatment  is  found  most  effec- 
tive which  is  also  indicated  for  the  general  good  of 
the  patient.  It  should  include  nutritious  food,  sun- 
shine, sleep,  change,  tonics,  etc.,  as  are  required  alike 
for  constitutional  and  local  derangements. 
12  * 


CHAPTER    XIX. 

REPARATIVE   TREATMENT. 

THE  first  effort  in  the  treatment  of  caries  should  be 
directed  to  tlie  predisposing  and  exciting  causes, 
constitutional  and  local.  The  object  of  treatment  is 
the  arrest  of  the  destructive  action,  and  the  repair  of 
the  damage  in  the  manner  best  calculated  to  preserve 
the  tooth  or  teeth  in  a  serviceable  condition,  and 
to  protect  them  against  a  recurrence  of  the  decay. 
It  is,  of  course,  desirable  that  the  treatment  be  begun 
as  soon  as  possible  after  the  attack  occurs,  and  before 
any  considerable  progress  in  the  disintegration  of  the 
tooth-structure  has  been  made.  Very  often  a  small 
orifice  leads  to  an  unexpectedly  large  interior  cavity, 
and  when  the  dentist  is  consulted  the  preservation  of 
the  tooth  is  almost  or  quite  impossible.  Sometimes 
a  tendency  to  disintegration  is  manifested  in  all  of 
the  teeth,  showing  systemic  derangement ;  sometimes 
it  is  limited  to  a  pair  of  teeth,  showing  that  constitu- 
tional conditions  at  the  time  of  their  formation  have 
resulted  in  an  imperfect  texture,  and  consequently  in 
a  lessened  capability  of  resisting  tlie  action  of  destruc- 

138 


REPARATIVE    TREATMENT.  1 39 

tive  agents ;  sometimes  it  is  confined  to  a  single  tooth, 
in  which  case  the  explanation  is  probably  to  be  found 
in  its  relations  to  the  adjoining  teeth. 

When,  owing  to  the  character  and  progress  of  de- 
cay, and  its  appearance  about  the  same  time  in  teeth 
formed  at  different  periods,  there  is  reason  to  believe 
that  it  is  an  expression  of  constitutional  disturbance, 
such  systemic  treatment  should  be  adopted  as  will 
promote  a  healthy  condition  of  the  secretions  of  the 
mouth  and  of  the  soft  tissues  about  the  teeth.  All 
deposits  and  accumulations  of  whatever  character 
about  the  teeth  should  be  carefully  and  thoroughly  re- 
moved, and  such  local  correctives  employed  as  may 
be  indicated,  conjoined  with  the  utmost  care  as  to 
constant  cleanliness.  Any  merely  mechanical  treat- 
ment of  carious  teeth  which  ignores  their  original 
organization,  their  special  condition,  and  the  tempera- 
ment, age,  and  constitutional  condition  of  the  patient, 
is  not  likely  to  be  successful.  These  are  considera- 
tions which  must  always  enter  into  the  calculation  in 
reference  to  methods  of  treatment.  There  is  no  greater 
folly  than  to  demand  the  following  of  stated  formulae, 
prescribed  manipulations,  and  an  unvarying  routine 
for  every  operation  without  regard  to  varieties  of  struct- 
ure and  character  of  decay.  Whether  to  fill  or  file, 
with  what  and  how  much,  must  be  determined  by 
the  dentist  chiefly  by  the  peculiarities  of  each  case. 
Until  the  influence  of  such  considerations  is  better 


140  THE   MOUTH  AND    THE    TEETH. 

understood  by  the  community  unjust  prejudices  and 
conclusions  will  prevail.  The  relative  cost  of  differ- 
ent materials  and  methods  must  also  be  considered, 
though  the  most  costly  operations  are  by  no  means 
always  the  best  so  far  as  the  salvation  of  the  teeth  is 
concerned. 

It  is  not  proposed,  however,  to  discuss  here  the  rela- 
tive value  of  special  materials  or  methods.  Though 
in  one  respect  all  who  are  worthy  the  name  of  dentist 
agree  —  viz.,  that  their  mission  is  not  to  remove  and 
substitute,  but  to  preserve  and  repair,  yet,  all  the  facts 
of  experience  which  have  been  gathered,  all  the  im- 
proved modes  of  practice  which  the  best  men  in  the 
profession  have  thus  far  developed,  have  not  sufficed 
to  establish  a  system  the  practice  of  which  will  in- 
fallibly prevent  or  arrest  the  progress  of  decay  in 
human  teeth.  The  most  earnest  and  conscientious, 
the  most  experienced  and  accomplished  operators 
disagree  notably  in  their  conceptions  of  what  con- 
stitutes the  best  practice  ;  and  with  all  the  advantages 
of  modern  instruments,  appliances,  apparatuses,  ma- 
terials, and  methods,  they  find  their  best  efforts  at  times 
unsatisfactory  alike  to  them  and  to  their  patients.  It 
is,  therefore,  apparent  that  no  rules  can  be  laid  down 
which  will  be  applicable  alike  in  all  cases.  The  gen- 
eral reader  cannot  be  expected  to  judge  intelligently 
of  questions  on  which  the  ablest  and  most  observing 
practitioners  of  dentistry  differ  diametrically.     The 


REPARATIVE    TREATMENT.  I4I 

practice  of  anticipating  and  so  preventing,  or  of  re- 
moving, superficial  caries  by  so-called  judicious  sepa- 
ration of  the  teeth  is  ably  and  earnestly  advocated, 
and  also  ably  and  earnestly  denounced.  Gold  is  gen- 
erally considered  the  best  material  for  permanent 
fillings  —  those  intended  to  be  permanent ;  though 
in  many  cases  it  is  admitted  that  other  materials  are 
to  be  preferred.  There  are,  however,  many  prepara- 
tions of  gold,  having  distinct  and  different  qualities, 
and  many  methods  of  manipulating  them,  so  that 
there  are  more  differences  even  in  gold  fillings  than 
would  be  conceived  by  those  not  familiar  with  the 
subject.  Amalgam,  gutta-percha,  and  various  other 
plastic  fillings  have  undoubted  claims  to  consideration 
in  many  cases.  The  same  is  true  of  tin-foil.  But 
patients  are  not  ordinarily  qualified  to  judge  of  the 
relative  merits  of  the  various  materials  and  methods, 
nor  of  their  special  applicability  in  individual  cases, 
and  cannot  do  otherwise  than  to  select  an  earnest, 
conscientious,  intelligent  dentist,  and  submit  to  his 
judgment  —  very  certain  to  be  better  than  their  own 
—  and  having  done  so,  to  give  him  all  the  help  in 
their  power  to  secure  the  good  results  desired  by  both. 
Good  operations  of  any  and  all  classes  fail  often 
because  of  a  want  of  cleanliness  on  the  part  of  the 
patient.  If  the  teeth  decay  because  of  unhealthy 
conditions  of  the  mouth,  produced  either  by  consti- 
tutional causes  or  from  want  of  cleanliness,  a  contin- 


142  THE  MOUTH  AND    THE    TEETH. 

uance  of  the  same  influences  will  produce  like  results 
after  the  most  thorough  and  most  conservative  treat- 
ment according  to  any  system.  A  tooth  that  has 
been  filled  or  filed  is  not  therefore  to  be  supposed 
invulnerable  to  the  attacks  of  destructive  agents, 
and  the  dentist  should  not  be  held  responsible  for 
the  patient's  neglect.  As  a  sick  man  requires  more 
care  than  a  well  one,  so  a  damaged  tooth,  even 
though  repaired,  needs  more  attention  than  a  sound 
one. 


CHAPTER   XX. 

SUBSTITUTION ARTIFICIAL    DENTURES. 

WHEN  the  natural  teeth  have  been  lost,  the  defi- 
ciency should  be  supplied  by  substitutes.  The 
comfort,  the  health,  the  speech,  and  the  personal  ap- 
pearance of  the  individual  will  be  promoted  thereby, 
provided  that  the  substitution  is  skilfully  and  artisti- 
cally accomplished.  Those  who  have  parted  with 
some  of  their  teeth  are  inclined  to  set  a  higher  value 
on  those  which  remain,  and  supplying  the  place  of 
the  missing  ones  is  often  the  best  means  of  preserv- 
ing the  rest — preventing  their  elongation  and  irregu- 
larity. When  the  molars  and  bicuspids  have  been 
removed  the  front  teeth  are  apt  to  project,  present- 
ing an  unsightly  appearance.  This  may  to  a  great 
extent  be  prevented  by  supplying  artificial  masticating 
surfaces. 

There  are  various  bases  for  artificial  dentures  — 
gold,  platinum,  porcelain,  silver,  rubber,  celluloid, 
etc.  Which  of  these  materials  is  the  best  in  a  given 
case  depends  upon  a  variety  of  circumstances  —  the 
extent  and  character  of  the  loss  to  be  supplied,  the 

143 


144  ^-^^  MOUTH  AND    THE    TEETH. 

age  and  ph^ysical  characteristics  of  the  patient,  the 
condition  of  the  mouth,  the  special  qualifications  of 
the  dentist,  and  the  length  of  the  patient's  purse. 
No  one  of  the  bases  named  is  always  the  best ;  each 
of  them  has  peculiar  fitness  for  special  cases.  No 
authoritative  opinion  governing  all  cases  can  there- 
fore be  given.  As  a  general  rule,  however,  it  may- 
be affirmed  that  a  gold  base  has  more  advantages 
and  fewer  disadvantages,  certainly  for  partial  sets, 
than  any  other  material. 

The  time  most  favorable  for  the  insertion  of  artifi- 
cial teeth  is  as  soon  after  the  loss  of  the  natural  ones 
as  the  state  of  the  mouth  will  allow,  and  before  the 
muscles  of  expression  have  been  suffered  to  lose  their 
natural  action.  It  is  the  modification  which  these 
muscles  undergo  after  the  extraction  of  the  teeth 
which  causes  the  changed  and  unnatural  appearance 
of  the  mouth  and  face  when  a  considerable  time 
elapses  before  the  natural  teeth  are  substituted  by 
others.  Their  prompt  replacement  will  also  tend 
greatly  to  prevent  the  elongation  or  protrusion  from 
their  sockets  of  the  teeth  which  formerly  occluded 
with  the  missing  ones. 

The  most  important  office  of  artificial  teeth,  as  well 
as  of  natural  ones,  is  the  mastication  of  food.  The 
proper  performance  of  this  function  is  indeed  essen- 
tial, and  frequently  the  skill  of  the  dentist  is  re- 
warded   by  a  restoration  to  health  of  those  whose 


SUBSTITUTION—  ARTIFICIAL   DENTURES.    1 45 

imperfect  mastication  previous  to  the  insertion  of 
artificial  teeth  had  entailed  upon  them  all  the  evils 
of  indigestion. 

The  sense  of  fatigue  in  the  jaws  and  muscles  of  the 
face,  caused  by  inability  to  close  the  mouth  properly, 
in  the  absence  of  opposing  or  occluding  teeth,  is  also 
overcome  by  the  skilful  substitution  of  artificial  teeth. 
The  enunciation  is  likewise  improved,  in  many  cases 
being  made  as  perfect  as  before. 

Sometimes,  in  the  case  of  elderly  people  who  have 
lost  their  teeth,  there  is  a  modification  of  the  lower 
jaw  which  causes  it  to  interfere  with  the  auditory  ap- 
paratus in  such  a  manner  as  to  produce  partial  or  ab- 
solute deafness,  which  the  insertion  of  a  properly 
constructed  denture  promptly  relieves.  Another  ad- 
vantage gained  by  the  wearing  of  artificial  teeth  is 
that  they  act  as  a  dam  in  preventing  the  sudden  emp- 
tying of  the  column  of  air  in  the  mouth  in  speaking 
—  explained  in  the  chapter  on  ''The  Mouth." 

The  modification  of  the  features  caused  by  the  re- 
moval of  the  supports  of  the  lips  and  cheeks  is,  of 
course,  changed  by  the  insertion  of  artificial  teeth ; 
but  whether  the  change  is  an  improvement  or  other- 
wise depends  upon  the  artistic  perceptions  of  the 
dentist.  It  is  unquestionable  that  the  majority  of 
the  dental  profession  have  given  more  thought  and 
labor  to  the  best  methods  of  restoring  impaired  func- 
tions—  securing  comfort,  usefulness,  and  durability 
13  K 


146  THE   MOUTH  AND    THE    TEETH. 

in  artificial  dentures  —  than  to  the  important  ques- 
tion of  correlation  of  the  substitutes  with  the  general 
physical  characteristics  of  the  patient.  To  this  ac- 
count is  to  be  charged  the  unseemly  incongruities 
constantly  staring  the  observer  in  the  face  from 
mouths  whose  natural  organs  have  been  replaced  in 
disregard  of  the  universal  law  of  correspondence. 
No  matter  how  anatomically  correct  or  how  skilfully 
adapted  for  speech  and  mastication  an  artificial  den- 
ture may  be,  if  it  does  not  bear  the  relation  demanded 
by  age,  temperament,  facial  contour,  etc.,  its  artifi- 
ciality will  be  apparent  to  every  beholder.  This  law 
of  correlation  running  through  nature  attracts  and 
enchants  us  in  an  infinite  diversity  of  manifestations. 
The  failure  in  art  to  recognize  its  demands  is  cor- 
respondingly abhorrent  to  our  sensibilities.  This  law 
of  correspondence,  apparent  throughout  the  organism, 
establishes  a  harmony  between  the  teeth  and  other 
physical  characteristics  by  which  we  are  led  to  infer 
their  size,  shape,  color,  and  structure.  A  broad  and 
square  or  an  oval  face ;  a  large,  coarse-featured  man, 
or  a  delicately  organized  woman ;  a  miss  of  eighteen, 
or  a  matron  of  fifty;  a  brunette  or  a  blonde  —  these 
and  other  varieties  present  as  many  differing  types, 
with  teeth  corresponding  in  size,  shape,  color,  and 
density.  If,  then,  teeth  correlated  in  their  charac- 
teristics to  those  which  nature  assigns  to  one  class 
be  inserted  in  the  mouth  of  one  whose  physical  or- 


SUBSTITUTION—  ARTIFICIAL    DENTURES.    1 4/ 

ganization  demands  a  different  style,  the  effect  can- 
not be  otherwise  than  displeasing  to  the  eye,  whether 
the  observer  be  skilled  in  perception  or  only  intui- 
tively recognizes  inharmony  without  understanding 
the  cause.  It  is  entirely  possible,  by  the  study  of 
aesthetic  anatomy,  for  the  skilled  dental  mechanician 
to  adapt  teeth  to  the  great  varieties  of  facial  expres- 
sion, to  avoid  offending  the  eye  trained  to  observe 
nature,  and  to  add  to  usefulness  the  charm  of  beauty. 
Incongruity  or  want  of  proper  expression  in  a  set  of 
teeth  shows  either  malpractice  in  him  by  whom  they 
were  selected  and  arranged,  or  dictation  on  the  part 
of  the  patient. 

But,  important  as  are  the  aesthetics  of  substitution, 
use  and  comfort  are  mainly  to  be  considered.  An 
artificial  denture  must  be  properly  constructed  and 
skilfully  adapted,  or  it  will  be  worse  than  useless. 
Badly-fitting  plates  cause  serious  affections  not  only 
of  the  soft  tissues  of  the  mouth,  but  frequently  of 
the  hard  palate  and  of  the  jaws.  However  correct 
artificial  teeth  may  be  in  their  aesthetic  relations, 
however  comfortable  and  useful,  let  no  one  be  be- 
guiled into  a  willing  sacrifice  of  the  natural  teeth 
for  the  sake  of  the  greater  comeliness  of  substitutes, 
or  because  the  latter  cannot  ache.  The  best  set  of 
artificial  teeth  that  ever  was  made  is  so  far  inferior 
to  an  average  natural  denture  that  the  two  can  only 
be  contrasted,  not  compared. 


INDEX. 


PAGE 

Acid  medicines,  injurious  action 

of,  upon  the  teeth iii,  135 

Alveolar  processes,   description 

of. 26 

Anatomy  of  the  teeth 32 

Antrum 24 

Artificial  dentures 143 

Bleeding  following  extraction, 
treatment  of. 124 

following  lancing,  treatment 

of. 59 

Caries no 

Cementum,  description  of. 33 

Cleft-palate 25,  95 

Correspondence,  law  of. 146 

Decay  of  the  teeth,  causes  of...   no 

varieties  of 113 

relations  of,  to  systemic  con- 
ditions   114 

Defects  of  teeth,  constitutional..     94 

of  enamel 96,  97 

Dentine,  description  of. 33 

Diet  proper  for  children 82 

DifEcuIt     dentition,     symptoms 

of. 50,  74 

earache  from 53 


page 

Enamel,  description  of. 33 

Epiglottis 16 

Eruption  of  the  teeth,  indications 
of. 54 

Fifth  nerve 86 

Food    containing    mineral     ele- 
ments      81 

importance  of,  during  ges- 
tation      79 

importance  of,  while  nurs- 
ing      79 

relations  of  the  teeth  to  ..  78,  80 

starchy,  injurious  to  young 

children 82 

Glands,  mucou"? 14,  19 

salivary 17 

Gum-boil 121 

Gum,  description  of 23 

Hare-lip 25,  95 

Hygiene  of  the  mouth 126 

Irregularities    of   the    teeth, 

causes  of. 98 

correction  of 104 

148 


INDEX. 


149 


PAGE 

Jaw,  angles  of  the,  at  various 

ages 25 

articulation    or  jointing    of 

the  lower 26 

description  of  the  lower 25 

"          "    "    upper 24 

Lancing,  hemorrhage  from 59 

methods  of. 57 

objections  against 56 

reasons  for 54 

Law  of  correspondence 146 

Lips,  description  of. 14 

Mastication 28 

beneficial  effects  of,  upon  the 

teeth 30 

effects  of  improved  facilities 

for 30 

results  of  imperfect 29 

Mouth,  anatomy  of  the 13 

Mouth-washes 128 

Nerves,  functions  of. 85 

Neuralgia 92,  117 

Palate,  hard  and  soft 14 

Pericementum 27 

Periodontitis 119 

Pharynx 15 

Precocious  mental  development, 

cause  of  irregularity 103 

Pulp,  description  of. 34 

exposure  of n8 

13* 


page 

Ranula,  how  produced 23 

Reparative  treatment 138 

Rheumatism,  toothache  from.  92,119 
Roots,  importance  of  the  reten- 
tion of. 77 


Saliva,  description  of. 19 

effects  of,  on  starchy  food..  20,  82 

modification   of,  in  disease 

21,  114 

relation  of,  to  the  sense  of 

hearing 20 

Salivary  calculus 106 

Shedding  of  the  temporary  teeth..     68 

Sixth-year  molars 64 

Sugar,  effects  of,  upon  the  teeth..  116 


Tartar,  sources  of 106 

treatment  of. 108 

varieties  of 107 

Teeth,  absorption  of  the  roots  of 

the  temporary 70 

anatomy  of. 32 

arrangement  of 41 

as  conservators  of  the  lungs..     31 

brushes 62,  130 

care  of  the  temporary 60 

circumstances      demanding 

extra  care  of 22,  73,  79,  137 

classification  of. 36 

danger  of  the  premature  ex- 
traction of  the  temporary' 61 

description  of 38 

development  of. 44 

difficult  eruption  of  the  wis- 
dom      74 

eruption  of  the  permanent..     63 

"         "     "    temporary..     47 


ISO 


INDEX. 


PAGE 

Teeth,  evils   from   decay  of  the 

temporary 6i 

• in  classification  of  animals..  32 

irregularities  of. 98 

names  of  their  surfaces 41 

nervous  relations  of. 84 

nutrition  of 76 

peculiarities,  varieties,  and 

defects  of. 94 

reflex  pain  in  and  from..  86,89,90 

shedding    of    the    tempo- 
rary   68 

special  care  of  the,  in  sick- 
ness   22 

sympathetic  affections  of...  90 


PAGE 

Teeth,     systemic     disturbances 

from  89 

Thumb-sucking,  results  of 100 

Tongue,  functions  of. 15 

in  disease 16 

ulcers  of  the,  caused  by  ca- 
rious teeth 16 

Toothache,  causes  of 92,  117 

treatment  of 122 

Tooth-powders 129,  134 

Tooth-soap 132 


Wisdom  teeth,  difficult  eruption 
of. 74 


The  End. 


DENTAL   VS^ORKS. 


Harris's  Principles  and  Practice  of  Dentistry.  Tenth 
Revised  Edition.  In  great  part  Rewritten,  Rearranged,  and  with 
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Harris's  Dictionary  of  Medical  Terminolog-y,  Dental 
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carefully  Revised  and  Enlarged.  By  Fp:rdinand  J.  S.  Gorgas, 
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etc.,  etc.     Royal  octavo.     Price,  in  cloth,  $6.50;  in  leather,  $7.50. 

Wedl'S  Pathology  of  the  Teeth.  With  Special  Reference  to 
their  Anatomy  and  Physiology.  Translated  by  W.  E.  Boardman, 
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Dental  Caries,  and  its  Causes.  An  Investigation  into  the  In- 
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A  System  of  Dental  Surgery.  By  John  Tomes,  F.R.S.,  late 
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Handy's  Text-Book  of  Anatomy,  and  Guide  to  Dis- 
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DENTAl.    WORKS. 


A  Manual  of  Dental  Anatomy,  Human  and  Compar- 
ative. By  Charles  S.  Tomes,  M.A.,  Lecturer  on  Dental  Anatomy 
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Hunter's  Meclianical  Dentistry.  A  Practical  Treatise  on  the 
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A  Practical  Treatise   on  Operative   Dentistry.     Third 

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The  Student's  Guide  to  Dental  Anatomy  and  Surgery 
and  tbe  Extraction  of  Teetli.  With  Illustrations.  By 
Henry  E.  Sewill,  M.R.C.S.,  Eng.,  L.D.S.,  Dental  Surgeon  to  the 
West  London  Hospital.     Price,  $1.50. 

A  Manual  of  Dental  Mechanics.  Containing  the  Preparation 
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Paris  and  Metal,  etc.,  etc.  By  James  Oakley  Coles,  D.D.S.,  etc. 
With  140  Illustrations.     Price,  $2.00. 

Elements  of  Dental  Materia  Medica  and  Therapeu- 
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BENNETT  ON  NUTRITION.     In  Health  and  Disease.     Second  Edition,  Re-   " 
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BENNETT  ON  CONSUMPTION.      Its  Treatment  by  Hygiene,  Climate  and 

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MADDEN'S  HEALTH  RESORTS  OF  EUROPE  AND  AFRICA,  including 

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ACTON'S  FUNCTIONS  AND  DISORDERS  OF  THE  REPRODUCTIVE 
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WILSON'S  ^GEORGE,  M.D.)  HAND-BOOK  OF  HYGIENE  AND  SANI- 
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WILSON,  DOMESTIC  HYGIENE.     Its  Principles  and  Practice.     In  Press. 

WILSON   ERASMUS)  ON  THE  SKIN  AND  HAIR.     Eighth  Edition i.oo 

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LOXAM'S    LABORATORY    TEACHING;    or,    Progressive    Exercises    in 
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FRANKLAND'S  HOW  TO  TEACH  CHEMISTRY.     Illustrated 1.25 

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HUFELAND  ON  THE  ART  OF  PROLONGING  LIFE.  Edited  by  Eras- 
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